Slippy map tilenames

Tile numbering for zoom=2

This article describes the file naming conventions for the Slippy Map application in the OpenStreetMap website.

• Tiles are 256 × 256 pixel PNG files
• Each zoom level is a directory, each column is a subdirectory, and each tile in that column is a file
• Filename (URL) format is /zoom/x/y.png

The slippy map expects tiles to be served up at URLs following this scheme, so all tile server URLs look pretty similar.

Tile servers

It has been proposed that this page or section be merged with TMS. (Discuss)

The first part of the URL specifies the tile server. The tile coordinates are typically specified by /zoom/x/y.png tail. Some tileservers will use a directory (e.g. "/cycle/") to specify a particular stylesheet. (Historically several subdomains were often provided to get around browser limitations on the number of simultaneous HTTP connections to each host - such as a.tile, b.tile, c.tile - but this is less important with modern browsers.)

Here are some examples:

Name	URL template	zoomlevels
OSM 'standard' style	https://tile.openstreetmap.org/zoom/x/y.png	0-19
OpenCycleMap	http://[abc].tile.thunderforest.com/cycle/zoom/x/y.png	0-22
Thunderforest Transport	http://[abc].tile.thunderforest.com/transport/zoom/x/y.png	0-22
MapTiles API Standard	https://maptiles.p.rapidapi.com/local/osm/v1/zoom/x/y.png?rapidapi-key=YOUR-KEY	0-19 globally
MapTiles API English	https://maptiles.p.rapidapi.com/en/map/v1/zoom/x/y.png?rapidapi-key=YOUR-KEY	0-19 globally with English labels

Further tilesets are available from various '3rd party' sources.

Zoom levels

The zoom parameter is an integer between 0 (zoomed out) and 18 (zoomed in). 18 is normally the maximum, but some tile servers might go beyond that.

zoom level	tile coverage	number of tiles	tile size(*) in degrees
0	1 tile covers whole world	1 tile	360° x 170.1022°
1	2 × 2 tiles	4 tiles	180° x 85.0511°
2	4 × 4 tiles	16 tiles	90° x [variable]
n	2n × 2n tiles	22n tiles	360/2n° x [variable]
12	4096 x 4096 tiles	16 777 216	0.0879° x [variable]
16		232 ≈ 4 295 million tiles
17		17.2 billion tiles
18		68.7 billion tiles
19	Maximum zoom for Mapnik layer	274.9 billion tiles

(*) While the width (longitude) in degrees is constant, given a zoom level, for all tiles, this does not happen for the height. In general, tiles belonging to the same row have equal height in degrees, but it decreases moving from the equator to the poles.

See Zoom levels for more details

Derivation of tile names

The following is identical to the well-known Web Mercator projection.

• Reproject the coordinates to the Spherical Mercator projection (from EPSG:4326 to EPSG:3857):
  • x = lon
  • y = arsinh(tan(lat)) = log[tan(lat) + sec(lat)]

  (lat and lon are in radians)

• Transform range of x and y to 0 – 1 and shift origin to top left corner:
  • x = [1 + (x / π)] / 2
  • y = [1 − (y / π)] / 2
• Calculate the number of tiles across the map, n, using 2^zoom
• Multiply x and y by n. Round results down to give tilex and tiley.

Implementations

Pseudo-code

For those who like pseudo-code, here's some hints:

sec = 1/cos
arsinh(x) = log(x + (x^2 + 1)^0.5)
sec^2(x) = tan^2(x) + 1
→ arsinh(tan(x)) = log(tan(x) + sec(x))

Please note that "log" represents the natural logarithm (also known as ln or log_e), not decimal logarithm (log₁₀), as used on some calculators.

Lon./lat. to tile numbers

n = 2 ^ zoom
xtile = n * ((lon_deg + 180) / 360)
ytile = n * (1 - (log(tan(lat_rad) + sec(lat_rad)) / π)) / 2

Tile numbers to lon./lat.

n = 2 ^ zoom
lon_deg = xtile / n * 360.0 - 180.0
lat_rad = arctan(sinh(π * (1 - 2 * ytile / n)))
lat_deg = lat_rad * 180.0 / π

This code returns the coordinate of the _upper left_ (northwest-most)-point of the tile.

Mathematics

Idem with mathematic signs (lat and lon in degrees):

Example: Convert a GPS coordinate to a pixel position in a Web Mercator tile

This example shows how to determine which tile (and what pixel coordinate within the tile) the Hachiko Statue near the Shibuya scramble crossing can be found in:

https://www.openstreetmap.org/node/597685675

1. Choose the coordinates you are interested in

Variable	Formula	Example (Hachiko Statue)
lonEPSG:4326	The familiar "GPS"-style longitude, which is recorded on a Node in OpenStreetMap. Positive is east, negative is west.	+139.7006793°
latEPSG:4326	The familiar "GPS"-style latitude, which is recorded on a Node in OpenStreetMap. Positive is north, negative is south.	+35.6590699°

2. Convert the coordinate to the Web Mercator projection (https://epsg.io/3857)

Variable	Formula	Example (Hachiko Statue)
xEPSG:3857	lonEPSG:4326 This value will fall in the range (-180°, 180°).	139.7006793°
yEPSG:3857	ln(tan(latEPSG:4326) + 1 / cos(latEPSG:4326)) OR, equivalently, arsinh(tan(latEPSG:4326)) This value will fall in the range (-π, π) for latitudes between 85.0511 °S and 85.0511 °N. For the curious, the number 85.0511 is the result of arctan(sinh(π)). By using this bound, the entire map becomes a (very large) square.	0.66693624687

3. Transform the projected point onto the unit square

Variable	Formula	Example (Hachiko Statue)
x	0.5 + xEPSG:3857 / 360° This value will fall in the range (0, 1). x=0 is the left (180° west) edge of the map. x=1 is the right (180° east) edge of the map. x=0.5 is the middle, the prime meridian.	0.8880574425
y	0.5 − yEPSG:3857 / (2π) This value will fall in the range (0, 1). y=0 is the top (north) edge of the map, at 85.0511 °N. y=1 is the bottom (south) edge of the map, at 85.0511 °S. y=0.5 is the middle, the equator.	0.3938537996

4. Determine the zoom level and horizontal/vertical location of individual tiles

Variable	Formula	Example (Hachiko Statue)
zoom	At a zoom level of 0, the entire earth is shown in a single tile. At a zoom level of 18, detail is visible in individual city blocks.	18
N	2zoom This is the number of tiles horizontally or vertically from one edge of the map to the other.	262144
xtile	N * x The whole-number part of xtile is the "x" value of the tile overall. The fractional part of xtile indicates the internal horizontal position of the coordinate within that tile. The first tile will have a xtile=0, with a left edge at 180° W. The last tile will have a xtile=2zoom−1, with a right edge at 180° E.	232798.930207 tile x = 232798 fractional x = 93.02%
ytile	N * y The whole-number part of ytile is the "y" value of the tile overall. The fractional part of ytile indicates the internal vertical position of the coordinate within that tile. The first tile will have a ytile=0, with a top edge at 85.0511 °N. The last tile will have a ytile=2zoom−1, with a bottom edge at 85.0511 °S.	103246.410442 tile y = 103246 fractional y = 41.04%

This results in the following tile URL:

Variable	Formula	Example (Hachiko Statue)
URL	Most tile servers use a path similar to /(zoom)/(xtile)/(ytile).png.	https://tile.openstreetmap.org/18/232798/103246.png

5. Transform the projected point into tile space

Variable	Formula	Example (Hachiko Statue)
dimension	By convention, this is 256 pixels for "standard resolution" tiles. For "high resolution" or "retina" tiles, it's typically 512 pixels.	256 pixels
xpixel	fract(xtile) * dimension This is a number between 0 and dimension, which is the x offset of this coordinate within the tile.	238.1 px
ypixel	fract(xtile) * dimension This is a number between 0 and dimension, which is the y offset of this coordinate within the tile.	105.1 px

Common programming languages

show

Python

Lon./lat. to tile numbers

import math
def deg2num(lat_deg, lon_deg, zoom):
  lat_rad = math.radians(lat_deg)
  n = 1 << zoom
  xtile = int((lon_deg + 180.0) / 360.0 * n)
  ytile = int((1.0 - math.asinh(math.tan(lat_rad)) / math.pi) / 2.0 * n)
  return xtile, ytile

Tile numbers to lon./lat.

import math
def num2deg(xtile, ytile, zoom):
  n = 1 << zoom
  lon_deg = xtile / n * 360.0 - 180.0
  lat_rad = math.atan(math.sinh(math.pi * (1 - 2 * ytile / n)))
  lat_deg = math.degrees(lat_rad)
  return lat_deg, lon_deg

This returns the NW-corner of the square. Use the function with xtile+1 and/or ytile+1 to get the other corners. With xtile+0.5 & ytile+0.5 it will return the center of the tile.

See also tilenames.py and the 'mercantile' library

show

Ruby

Lon./lat. to tile numbers

def get_tile_number(lat_deg, lng_deg, zoom)
  lat_rad = lat_deg/180 * Math::PI
  n = 2.0 ** zoom
  x = ((lng_deg + 180.0) / 360.0 * n).to_i
  y = ((1.0 - Math::log(Math::tan(lat_rad) + (1 / Math::cos(lat_rad))) / Math::PI) / 2.0 * n).to_i
  
  {:x => x, :y =>y}
end

Tile numbers to lon./lat.

def get_lat_lng_for_number(xtile, ytile, zoom)
  n = 2.0 ** zoom
  lon_deg = xtile / n * 360.0 - 180.0
  lat_rad = Math::atan(Math::sinh(Math::PI * (1 - 2 * ytile / n)))
  lat_deg = 180.0 * (lat_rad / Math::PI)
  {:lat_deg => lat_deg, :lng_deg => lon_deg}
end

Same as the Python implementation above, this returns the NW-corner of the square. Use the function with xtile+1 and/or ytile+1 to get the other corners. With xtile+0.5 & ytile+0.5 it will return the center of the tile.

show

Perl

Lon./lat. to tile numbers

use Math::Trig;
sub getTileNumber {
  my ($lat,$lon,$zoom) = @_;
  my $xtile = int( ($lon+180)/360 * 2**$zoom ) ;
  my $ytile = int( (1 - log(tan(deg2rad($lat)) + sec(deg2rad($lat)))/pi)/2 * 2**$zoom ) ;
  return ($xtile, $ytile);
}

Tile numbers to lon./lat.

use Math::Trig;
sub Project {
  my ($X,$Y, $Zoom) = @_;
  my $Unit = 1 / (2 ** $Zoom);
  my $relY1 = $Y * $Unit;
  my $relY2 = $relY1 + $Unit;

  # note: $LimitY = ProjectF(degrees(atan(sinh(pi)))) = log(sinh(pi)+cosh(pi)) = pi
  # note: degrees(atan(sinh(pi))) = 85.051128..
  #my $LimitY = ProjectF(85.0511);

  # so stay simple and more accurate
  my $LimitY = pi;
  my $RangeY = 2 * $LimitY;
  $relY1 = $LimitY - $RangeY * $relY1;
  $relY2 = $LimitY - $RangeY * $relY2;
  my $Lat1 = ProjectMercToLat($relY1);
  my $Lat2 = ProjectMercToLat($relY2);
  $Unit = 360 / (2 ** $Zoom);
  my $Long1 = -180 + $X * $Unit;
  return ($Lat2, $Long1, $Lat1, $Long1 + $Unit); # S,W,N,E
}
sub ProjectMercToLat($){
  my $MercY = shift;
  return rad2deg(atan(sinh($MercY)));
}
sub ProjectF
{
  my $Lat = shift;
  $Lat = deg2rad($Lat);
  my $Y = log(tan($Lat) + sec($Lat));
  return $Y;
}

Lon./lat. to bbox

use Math::Trig;

sub getTileNumber {
    my ($lat,$lon,$zoom) = @_;
    my $xtile = int( ($lon+180)/360 * 2**$zoom ) ;
    my $ytile = int( (1 - log(tan(deg2rad($lat)) + sec(deg2rad($lat)))/pi)/2 * 2**$zoom ) ;
    return ($xtile, $ytile);
}

sub getLonLat {
	my ($xtile, $ytile, $zoom) = @_;
	my $n = 2 ** $zoom;
	my $lon_deg = $xtile / $n * 360.0 - 180.0;
	my $lat_deg = rad2deg(atan(sinh(pi * (1 - 2 * $ytile / $n))));
	return ($lon_deg, $lat_deg);
}

# convert from permalink OSM format like:
# https://www.openstreetmap.org/?lat=43.731049999999996&lon=15.79375&zoom=13&layers=M
# to OSM "Export" iframe embedded bbox format like:
# https://www.openstreetmap.org/export/embed.html?bbox=15.7444,43.708,15.8431,43.7541&layer=mapnik

sub LonLat_to_bbox {
	my ($lat, $lon, $zoom) = @_;

	my $width = 425; my $height = 350;	# note: must modify this to match your embed map width/height in pixels
	my $tile_size = 256;

	my ($xtile, $ytile) = getTileNumber ($lat, $lon, $zoom);

	my $xtile_s = ($xtile * $tile_size - $width/2) / $tile_size;
	my $ytile_s = ($ytile * $tile_size - $height/2) / $tile_size;
	my $xtile_e = ($xtile * $tile_size + $width/2) / $tile_size;
	my $ytile_e = ($ytile * $tile_size + $height/2) / $tile_size;

	my ($lon_s, $lat_s) = getLonLat($xtile_s, $ytile_s, $zoom);
	my ($lon_e, $lat_e) = getLonLat($xtile_e, $ytile_e, $zoom);

	my $bbox = "$lon_s,$lat_s,$lon_e,$lat_e";
	return $bbox;
}

show

PHP

Lon./lat. to tile numbers

$xtile = floor((($lon + 180) / 360) * pow(2, $zoom));
$ytile = floor((1 - log(tan(deg2rad($lat)) + 1 / cos(deg2rad($lat))) / pi()) /2 * pow(2, $zoom));

Tile numbers to lon./lat.

$n = pow(2, $zoom);
$lon_deg = $xtile / $n * 360.0 - 180.0;
$lat_deg = rad2deg(atan(sinh(pi() * (1 - 2 * $ytile / $n))));

show

ColdFusion

Lon./lat. to tile numbers

CFScript syntax:

<cfscript>
    function longitude2tile(longitude, zoom) {
	    return floor((longitude + 180) / 360 * (2 ^ zoom));
	    }

    function latitude2tile(latitude, zoom) {
	    return floor((1 - log(tan(latitude * pi() / 180) + 1 / cos(latitude * pi() / 180)) / pi()) / 2 * (2 ^ zoom));
	    }

    xtile = longitude2tile(longitude, zoom);
    ytile = latitude2tile(latitude, zoom);
</cfscript>

CFML syntax:

<cffunction name="longitude2tile" output="no" returntype="numeric">
	<cfargument name="longitude" type="numeric" required="yes" />
	<cfargument name="zoom" type="numeric" required="yes" />
	<cfreturn floor((arguments.longitude + 180) / 360 * (2 ^ arguments.zoom)) />
</cffunction>

<cffunction name="latitude2tile" output="no" returntype="numeric">
	<cfargument name="latitude" type="numeric" required="yes" />
	<cfargument name="zoom" type="numeric" required="yes" />
	<cfreturn floor((1 - log(tan(arguments.latitude * pi() / 180) + 1 / cos(arguments.latitude * pi() / 180)) / pi()) / 2 * (2 ^ arguments.zoom)) />
</cffunction>

<cfset xtile = longitude2tile(longitude, zoom) />
<cfset ytile = latitude2tile(latitude, zoom) />

Tile numbers to lon./lat.

CFScript syntax:

<cfscript>
    function tile2longitude(xtile, zoom) {
	    return (xtile / (2 ^ zoom) * 360 - 180);
	    }

    function tile2latitude(ytile, zoom) {
	    var n = pi() - 2 * pi() * ytile / (2 ^ zoom);
	    return (180 / pi() * atn(0.5 * (exp(n) - exp(-n))));
	    }

    longitude = tile2longitude(xtile, zoom);
    latitude = tile2latitude(ytile, zoom);
</cfscript>

CFML syntax:

<cffunction name="tile2longitude" output="no" returntype="numeric">
	<cfargument name="xtile" type="numeric" required="yes" />
	<cfargument name="zoom" type="numeric" required="yes" />
	<cfreturn (arguments.xtile / (2 ^ arguments.zoom) * 360 - 180) />
</cffunction>

<cffunction name="tile2latitude" output="no" returntype="numeric">
	<cfargument name="ytile" type="numeric" required="yes" />
	<cfargument name="zoom" type="numeric" required="yes" />
	<cfset var n = pi() - 2 * pi() * arguments.ytile / (2 ^ arguments.zoom) />
	<cfreturn (180 / pi() * atn(0.5 * (exp(n) - exp(-n)))) />
</cffunction>

<cfset longitude = tile2longitude(xtile, zoom) />
<cfset latitude = tile2latitude(ytile, zoom) />

show

ECMAScript (JavaScript/ActionScript, etc.)

 function lon2tile(lon,zoom) { return (Math.floor((lon+180)/360*Math.pow(2,zoom))); }
 function lat2tile(lat,zoom)  { return (Math.floor((1-Math.log(Math.tan(lat*Math.PI/180) + 1/Math.cos(lat*Math.PI/180))/Math.PI)/2 *Math.pow(2,zoom))); }

Inverse process:

 function tile2long(x,z) {
  return (x/Math.pow(2,z)*360-180);
 }
 function tile2lat(y,z) {
  var n=Math.PI-2*Math.PI*y/Math.pow(2,z);
  return (180/Math.PI*Math.atan(0.5*(Math.exp(n)-Math.exp(-n))));
 }

Example for calculating number of tiles within given extent and zoom-level:

var zoom        = 9;
var top_tile    = lat2tile(north_edge, zoom); // eg.lat2tile(34.422, 9);
var left_tile   = lon2tile(west_edge, zoom);
var bottom_tile = lat2tile(south_edge, zoom);
var right_tile  = lon2tile(east_edge, zoom);
var width       = Math.abs(left_tile - right_tile) + 1;
var height      = Math.abs(top_tile - bottom_tile) + 1;

// total tiles
var total_tiles = width * height; // -> eg. 377

Example: Tilesname WebCalc V1.0

Lon./lat. to bbox

const EARTH_CIR_METERS = 40075016.686;
const TILE_SIZE = 256
const degreesPerMeter = 360 / EARTH_CIR_METERS;
const LIMIT_Y = toDegrees(Math.atan(Math.sinh(Math.PI))) // around 85.0511...

function toRadians(degrees) {
  return degrees * Math.PI / 180;
}
function toDegrees(radians) {
  return (radians / Math.PI) * 180
}

function tile2long(x,z) {
  return (x/Math.pow(2,z)*360-180);
}

function lonOnTile(lon, zoom) {
  return ((lon + 180) / 360) * Math.pow(2, zoom)
}
function tile2lat(y,z) {
  const n=Math.PI-2*Math.PI*y/Math.pow(2,z);
  return (180/Math.PI*Math.atan(0.5*(Math.exp(n)-Math.exp(-n))));
}

function latOnTile(lat, zoom) {
  return (
    ((1 -
      Math.log(
        Math.tan((lat * Math.PI) / 180) + 1 / Math.cos((lat * Math.PI) / 180)
      ) /
        Math.PI) /
      2) *
    Math.pow(2, zoom)
  )
}
 

function latLngToBounds(lat, lng, zoom, width, height){ // width and height must correspond to the iframe width/height
  const metersPerPixelEW = EARTH_CIR_METERS / Math.pow(2, zoom + 8);

  const shiftMetersEW = width/2 * metersPerPixelEW;

  const shiftDegreesEW = shiftMetersEW * degreesPerMeter;
  
  const southTile = (TILE_SIZE * latOnTile(lat, zoom) + height/2) / TILE_SIZE
  const northTile = (TILE_SIZE * latOnTile(lat, zoom) - height/2) / TILE_SIZE


  return {
    south: Math.max(tile2lat(southTile, zoom), -LIMIT_Y),
    west: lng-shiftDegreesEW,
    north: Math.min(tile2lat(northTile, zoom), LIMIT_Y),
    east: lng+shiftDegreesEW
  }
}

// Usage Example: create the src attribute for Open Street Map:
const latitude = 47
const longitude = 12
const zoom = 16
const width = 450
const height = 350

const bb = latLngToBounds(latitude,longitude,zoom,width,height);

const src = [
  "https://www.openstreetmap.org/export/embed.html?bbox=",
  bb.west,
  ",",
  bb.south,
  ",",
  bb.east,
  ",",
  bb.north,
  "&layer=mapnik&marker=",
  latitude,
  ",",
  longitude,
].join('');

show

C/C++

int long2tilex(double lon, int z) 
{ 
	return (int)(floor((lon + 180.0) / 360.0 * (1 << z))); 
}

int lat2tiley(double lat, int z)
{ 
    double latrad = lat * M_PI/180.0;
	return (int)(floor((1.0 - asinh(tan(latrad)) / M_PI) / 2.0 * (1 << z))); 
}

double tilex2long(int x, int z) 
{
	return x / (double)(1 << z) * 360.0 - 180;
}

double tiley2lat(int y, int z) 
{
	double n = M_PI - 2.0 * M_PI * y / (double)(1 << z);
	return 180.0 / M_PI * atan(0.5 * (exp(n) - exp(-n)));
}

show

C#

int long2tilex(double lon, int z)
{
    return (int)(Math.Floor((lon + 180.0) / 360.0 * (1 << z)));
}

int lat2tiley(double lat, int z)
{
    var latRad = lat / 180 * Math.PI;
    return (int)Math.Floor((1 - Math.Log(Math.Tan(latRad) + 1 / Math.Cos(latRad)) / Math.PI) / 2 * (1 << z));
}

double tilex2long(int x, int z)
{
    return x / (double)(1 << z) * 360.0 - 180;
}

double tiley2lat(int y, int z)
{
    double n = Math.PI - 2.0 * Math.PI * y / (double)(1 << z);
    return 180.0 / Math.PI * Math.Atan(0.5 * (Math.Exp(n) - Math.Exp(-n)));
}

show

Go

Example(Deg2num had changed below.) : [1] Doc : [2]

import (
	"math"
)

type Tile struct {
	Z    int
	X    int
	Y    int
	Lat  float64
	Long float64
}

type Conversion interface {
	deg2num(t *Tile) (x int, y int)
	num2deg(t *Tile) (lat float64, long float64)
}

func (*Tile) Deg2num(t *Tile) (x int, y int) {
	n := math.Exp2(float64(z))
	x = int(math.Floor((lon + 180.0) / 360.0 * n))
	if float64(x) >= n {
		x = int(n - 1)
	}
	y = int(math.Floor((1.0 - math.Log(math.Tan(lat*math.Pi/180.0)+1.0/math.Cos(lat*math.Pi/180.0))/math.Pi) / 2.0 * n))
	return
}

func (*Tile) Num2deg(t *Tile) (lat float64, long float64) {
	n := math.Pi - 2.0*math.Pi*float64(t.Y)/math.Exp2(float64(t.Z))
	lat = 180.0 / math.Pi * math.Atan(0.5*(math.Exp(n)-math.Exp(-n)))
	long = float64(t.X)/math.Exp2(float64(t.Z))*360.0 - 180.0
	return lat, long
}

show

Java

 public class slippytest {
 public static void main(String[] args) {
   int zoom = 10;
   double lat = 47.968056d;
   double lon = 7.909167d;
   System.out.println("https://tile.openstreetmap.org/" + getTileNumber(lat, lon, zoom) + ".png");
 }
 public static String getTileNumber(final double lat, final double lon, final int zoom) {
   int xtile = (int)Math.floor( (lon + 180) / 360 * (1<<zoom) ) ;
   int ytile = (int)Math.floor( (1 - Math.log(Math.tan(Math.toRadians(lat)) + 1 / Math.cos(Math.toRadians(lat))) / Math.PI) / 2 * (1<<zoom) ) ;
    if (xtile < 0)
     xtile=0;
    if (xtile >= (1<<zoom))
     xtile=((1<<zoom)-1);
    if (ytile < 0)
     ytile=0;
    if (ytile >= (1<<zoom))
     ytile=((1<<zoom)-1);
    return("" + zoom + "/" + xtile + "/" + ytile);
   }
 }

Tile bounding box

  class BoundingBox {
    double north;
    double south;
    double east;
    double west;   
  }
  BoundingBox tile2boundingBox(final int x, final int y, final int zoom) {
    BoundingBox bb = new BoundingBox();
    bb.north = tile2lat(y, zoom);
    bb.south = tile2lat(y + 1, zoom);
    bb.west = tile2lon(x, zoom);
    bb.east = tile2lon(x + 1, zoom);
    return bb;
  }

  static double tile2lon(int x, int z) {
     return x / Math.pow(2.0, z) * 360.0 - 180;
  }

  static double tile2lat(int y, int z) {
    double n = Math.PI - (2.0 * Math.PI * y) / Math.pow(2.0, z);
    return Math.toDegrees(Math.atan(Math.sinh(n)));
  }

show

Kotlin

import kotlin.math.*

fun getXYTile(lat : Double, lon: Double, zoom : Int) : Pair<Int, Int> {
        val latRad = Math.toRadians(lat)
        var xtile = floor( (lon + 180) / 360 * (1 shl zoom) ).toInt()
        var ytile = floor( (1.0 - asinh(tan(latRad)) / PI) / 2 * (1 shl zoom) ).toInt()

        if (xtile < 0) {
            xtile = 0
        }
        if (xtile >= (1 shl zoom)) {
            xtile= (1 shl zoom) - 1
        }
        if (ytile < 0) {
            ytile = 0
        }
        if (ytile >= (1 shl zoom)) {
            ytile = (1 shl zoom) - 1
        }

        return Pair(xtile, ytile)
}

show

VB.Net

Private Function CalcTileXY(ByVal lat As Single, ByVal lon As Single, ByVal zoom As Long) As Point
   CalcTileXY.X  = CLng(Math.Floor((lon + 180) / 360 * 2 ^ zoom))
   CalcTileXY.Y = CLng(Math.Floor((1 - Math.Log(Math.Tan(lat * Math.PI / 180) + 1 / Math.Cos(lat * Math.PI / 180)) / Math.PI) / 2 * 2 ^ zoom))
End Function

show

C#

		
public PointF WorldToTilePos(double lon, double lat, int zoom)
{
	PointF p = new Point();
	p.X = (float)((lon + 180.0) / 360.0 * (1 << zoom));
	p.Y = (float)((1.0 - Math.Log(Math.Tan(lat * Math.PI / 180.0) + 
		1.0 / Math.Cos(lat * Math.PI / 180.0)) / Math.PI) / 2.0 * (1 << zoom));
		
	return p;
}

public PointF TileToWorldPos(double tile_x, double tile_y, int zoom) 
{
	PointF p = new Point();
	double n = Math.PI - ((2.0 * Math.PI * tile_y) / Math.Pow(2.0, zoom));

	p.X = (float)((tile_x / Math.Pow(2.0, zoom) * 360.0) - 180.0);
	p.Y = (float)(180.0 / Math.PI * Math.Atan(Math.Sinh(n)));

	return p;
}

show

XSLT

Requires math extensions from exslt.org.

<xsl:transform
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
 xmlns:m="http://exslt.org/math"
 extension-element-prefixes="m"
 version="1.0">

 <xsl:output method="text"/>
 <xsl:variable name="pi" select="3.14159265358979323846"/>
 
 <xsl:template name="tiley">
 	<xsl:param name="lat"/>
 	<xsl:param name="zoomfact"/>
 	<xsl:variable name="a" select="($lat * $pi) div 180.0"/>
 	<xsl:variable name="b" select="m:log(m:tan($a) + (1.0 div m:cos($a)))"/>
 	<xsl:variable name="c" select="(1.0 - ($b div $pi)) div 2.0"/>
	<xsl:value-of select="floor($c * $zoomfact)"/>
 </xsl:template>
 
 <xsl:template name="tilename">
 	<xsl:param name="lat"/>
 	<xsl:param name="lon"/>
 	<xsl:param name="zoom" select="10"/>
 	<xsl:variable name="zoomfact" select="m:power(2,$zoom)"/>
 	<xsl:variable name="x" select="floor((360.0 + ($lon * 2)) * $zoomfact div 720.0)"/>
 	<xsl:variable name="y">
 		<xsl:call-template name="tiley">
 			<xsl:with-param name="lat" select="$lat"/>
 			<xsl:with-param name="zoomfact" select="$zoomfact"/>
 		</xsl:call-template>
 	</xsl:variable>
 	<xsl:value-of select="concat($zoom,'/',$x,'/',$y)"/>
 </xsl:template>
 
 <xsl:template match="/">
 	<xsl:call-template name="tilename">
 		<xsl:with-param name="lat" select="49.867731999999997"/>
 		<xsl:with-param name="lon" select="8.6295369999999991"/>
 		<xsl:with-param name="zoom" select="14"/>
 	</xsl:call-template>
 </xsl:template>
</xsl:transform>

show

Haskell

-- https://github.com/apeyroux/HSlippyMap

long2tilex lon z = floor((lon + 180.0) / 360.0 * (2.0 ** z))

lat2tiley lat z = floor((1.0 - log( tan(lat * pi/180.0) + 1.0 / cos(lat * pi/180.0)) / pi) / 2.0 * (2.0 ** z))

tilex2long x z = x / (2.0 ** z) * 360.0 - 180

tiley2lat y z = 180.0 / pi * atan(0.5 * (exp(n) - exp(-n)))
        where
                n = pi - 2.0 * pi * y / (2.0 ** z)

-- Example
main = do
        --print $ long2tilex 2.2712 17
        --print $ lat2tiley 48.8152 17
        --print $ tilex2long 66362 17
        --print $ tiley2lat 45115 17
        putStrLn "gps: (lat=48.8152,long=2.2712)"
        putStrLn $ "https://tile.openstreetmap.org/17/" ++ show x ++ "/" ++ show y ++ ".png"
        where
                z = 17
                x = long2tilex 2.2712 z
                y = lat2tiley 48.8152 z

show

Scala

import scala.math._

case class Tile(x: Int,y: Int, z: Short){
  def toLatLon = new LatLonPoint(
    toDegrees(atan(sinh(Pi * (1.0 - 2.0 * y.toDouble / (1<<z))))), 
    x.toDouble / (1<<z) * 360.0 - 180.0,
    z)
  def toURI = new java.net.URI("https://tile.openstreetmap.org/"+z+"/"+x+"/"+y+".png")
}

case class LatLonPoint(lat: Double, lon: Double, z: Short){
  def toTile = new Tile(
    ((lon + 180.0) / 360.0 * (1<<z)).toInt,
    ((1 - log(tan(toRadians(lat)) + 1 / cos(toRadians(lat))) / Pi) / 2.0 * (1<<z)).toInt, 
    z)
}

//Usage:
val point = LatLonPoint(51.51202,0.02435,17)
val tile = point.toTile
// ==> Tile(65544,43582,17)
val uri = tile.toURI
// ==> https://tile.openstreetmap.org/17/65544/43582.png

show

Revolution/Transcript

function osmTileRef iLat, iLong, iZoom --> part path
   local n, xTile, yTile
   put (2 ^ iZoom) into n
   put (iLong + 180) / 360 * n into xTile
   multiply iLat by (pi / 180) -- convert to radians
   put ((1 - ln(tan(iLat) + 1 / cos(iLat)) / pi) / 2) * n into yTile
   return "/" & iZoom & "/" & trunc(xTile) & "/" & trunc(yTile)
end osmTileRef

function osmTileCoords xTile, yTile, iZoom --> coordinates
   local twoPzoom, iLong, iLat, n
   put (2 ^ iZoom) into twoPzoom
   put xTile / twoPzoom * 360 - 180 into iLong
   put pi - 2 * pi * yTile / twoPzoom into n
   put "n1=" && n
   put 180 / pi * atan(0.5 * (exp(n) - exp(-n))) into iLat 
   return iLat & comma & iLong
end osmTileCoords

show

Mathematica / Wolfram Language

Deg2Num[lat_, lon_, zoom_] := 
 {IntegerPart[(2^(-3 + zoom)*(180 + lon))/45], IntegerPart[2^(-1 + zoom)*(1 - Log[Sec[Degree*lat] + Tan[Degree*lat]]/Pi)]}

Num2Deg[xtile_,ytile_,zoom_] := 
 {ArcTan[Sinh[Pi*(1 - 2*(ytile/2^zoom))]]/Degree, (xtile/2^zoom)*360 - 180} // N

show

Tcl

First of all, you need to use the package map::slippy from Tcllib:

package require map::slippy

Lat./lon. to tile number

map::slippy geo 2tile [list $zoom $lat $lon]

Tile number to lat/lon

map::slippy tile 2geo [list $zoom $row $col]

show

Pascal

(translated from the Python code above to Pascal)

Coordinates to tile numbers

uses {...}, Math;
{...}
var
  zoom: Integer;
  lat_rad, lat_deg, lon_deg, n: Real;
begin
  lat_rad := DegToRad(lat_deg);
  n := Power(2, zoom);
  xtile := Trunc(((lon_deg + 180) / 360) * n);
  ytile := Trunc((1 - (ln(Tan(lat_rad) + (1 /Cos(lat_rad))) / Pi)) / 2 * n);
end;

Tile numbers to coordinates

uses {...}, Math;
{...}
var
  lat_rad, n: Real;
begin
  n := Power(2, zoom);
  lat_rad := Arctan (Sinh (Pi * (1 - 2 * ytile / n)));
  lat_deg := RadtoDeg (lat_rad);
  lon_deg := xtile / n * 360.0 - 180.0;
end;

show

R

Coordinates to tile numbers

deg2num<-function(lat_deg, lon_deg, zoom){
  lat_rad <- lat_deg * pi /180
  n <- 2.0 ^ zoom
  xtile <- floor((lon_deg + 180.0) / 360.0 * n)
  ytile = floor((1.0 - log(tan(lat_rad) + (1 / cos(lat_rad))) / pi) / 2.0 * n)
  return( c(xtile, ytile))
#  return(paste(paste("https://tile.openstreetmap.org", zoom, xtile, ytile, sep="/"),".png",sep=""))
}

# Returns data frame containing detailed info for all zooms
deg2num.all<-function(lat_deg, lon_deg){
  nums <- as.data.frame(matrix(ncol=6,nrow=21))
  colnames(nums) <- c('zoom', 'x', 'y', 'mapquest_osm', 'mapquest_aerial', 'osm')
  rownames(nums) <- 0:20
  for (zoom in 0:20) {
    num <- deg2num(lat_deg, lon_deg, zoom)
    nums[1+zoom,'zoom'] <- zoom
    nums[1+zoom,'x'] <- num[1]
    nums[1+zoom,'y'] <- num[2]
    nums[1+zoom,'mapquest_osm'] <- paste('http://otile1.mqcdn.com/tiles/1.0.0/map/', zoom, '/', num[1], '/', num[2], '.jpg', sep='')
    nums[1+zoom,'mapquest_aerial'] <- paste('http://otile1.mqcdn.com/tiles/1.0.0/sat/', zoom, '/', num[1], '/', num[2], '.jpg', sep='')
    nums[1+zoom,'osm'] <- paste('https://tile.openstreetmap.org/', zoom, '/', num[1], '/', num[2], '.png', sep='')
  }
  return(nums)
}

show

Awk (Bourne shell)

Tile numbers to lat./lon. / Coordinates to tile numbers / Sample of usage, with optional tms-format support

xtile2long()
{
 xtile=$1
 zoom=$2
 echo "${xtile} ${zoom}" | awk '{printf("%.9f", $1 / 2.0^$2 * 360.0 - 180)}'
} 

long2xtile()  
{ 
 long=$1
 zoom=$2
 echo "${long} ${zoom}" | awk '{ xtile = ($1 + 180.0) / 360 * 2.0^$2; 
  xtile+=xtile<0?-0.5:0.5;
  printf("%d", xtile ) }'
}

ytile2lat()
{
 ytile=$1;
 zoom=$2;
 tms=$3;
 if [ ! -z "${tms}" ]
 then
 #  from tms_numbering into osm_numbering
  ytile=`echo "${ytile}" ${zoom} | awk '{printf("%d\n",((2.0^$2)-1)-$1)}'`;
 fi
 lat=`echo "${ytile} ${zoom}" | awk -v PI=3.14159265358979323846 '{ 
       num_tiles = PI - 2.0 * PI * $1 / 2.0^$2;
       printf("%.9f", 180.0 / PI * atan2(0.5 * (exp(num_tiles) - exp(-num_tiles)),1)); }'`;
 echo "${lat}";
}

lat2ytile() 
{ 
 lat=$1;
 zoom=$2;
 tms=$3;
 ytile=`echo "${lat} ${zoom}" | awk -v PI=3.14159265358979323846 '{ 
   tan_x=sin($1 * PI / 180.0)/cos($1 * PI / 180.0);
   ytile = (1 - log(tan_x + 1/cos($1 * PI/ 180))/PI)/2 * 2.0^$2; 
   ytile+=ytile<0?-0.5:0.5;
   printf("%d", ytile ) }'`;
 if [ ! -z "${tms}" ]
 then
  #  from oms_numbering into tms_numbering
  ytile=`echo "${ytile}" ${zoom} | awk '{printf("%d\n",((2.0^$2)-1)-$1)}'`;
 fi
 echo "${ytile}";
}
# ------------------------------------
# Sample of use: 
# Position Brandenburg Gate, Berlin
# ------------------------------------
LONG=13.37771496361961;
LAT=52.51628011262304;
ZOOM=17;
TILE_X=70406;
TILE_Y=42987; 
TILE_Y_TMS=88084;
TMS=""; # when NOT empty: tms format assumed
# ------------------------------------
# assume input/output of y is in oms-format:
LONG=$( xtile2long ${TILE_X} ${ZOOM} );
LAT=$( ytile2lat ${TILE_Y} ${ZOOM} ${TMS} );
# Result should be longitude[13.375854492] latitude[52.517892228]
TILE_X=$( long2xtile ${LONG} ${ZOOM} );
TILE_Y=$( lat2ytile ${LAT} ${ZOOM} ${TMS} );
# Result should be x[70406] y_oms[42987] 
# ------------------------------------
# assume input/output of y is in tms-format:
TMS="tms";
TILE_Y_TMS=$( lat2ytile ${LAT} ${ZOOM} ${TMS} );
LAT_TMS=$( ytile2lat ${TILE_Y_TMS} ${ZOOM} ${TMS} );
echo "Result should be y_oms[${TILE_Y}] latitude[${LAT}] ; y_tms[${TILE_Y_TMS}] latitude_tms[${LAT_TMS}] "
# latitude and latitude_tms should have the same value ; y_oms and y_tms should have the given start values:
# Result should be y_oms[42987] latitude[52.517892228] ; y_tms[88084] latitude_tms[52.517892228]
# ------------------------------------

Tile bounding box and center

n=$(ytile2lat `expr ${TILE_Y}` ${ZOOM})
s=$(ytile2lat `expr ${TILE_Y} + 1` ${ZOOM})
e=$(xtile2long `expr ${TILE_X} + 1` ${ZOOM})
w=$(xtile2long `expr ${TILE_X}` ${ZOOM})

echo "bbox=$w,$s,$e,$n" 
echo "-I-> Result should be [bbox=13.375854492,52.516220864,13.378601074,52.517892228]";

center_lat=`echo "$s $n" | awk '{printf("%.8f", ($1 + $2) / 2.0)}'`
center_lon=`echo "$w $e" | awk '{printf("%.8f", ($1 + $2) / 2.0)}'`

echo "center=$center_lat,$center_lon"
echo "-I-> Result should be [center=52.51705655,13.37722778]";

show

Octave

Lon./lat. to tile numbers

% convert the degrees to radians
rho = pi/180;
lon_rad = lon_deg * rho;
lat_rad = lat_deg * rho;

n = 2 ^ zoom
xtile = n * ((lon_deg + 180) / 360)
ytile = n * (1 - (log(tan(lat_rad) + sec(lat_rad)) / pi)) / 2

Tile numbers to lon./lat.

n=2^zoom
lon_deg = xtile / n * 360.0 - 180.0
lat_rad = arctan(sinh(pi * (1 - 2 * ytile / n)))
lat_deg = lat_rad * 180.0 / pi

show

Emacs-lisp

(defun longitude2tile (lon zoom) (* (expt 2 zoom) (/ (+ lon 180) 360)))

(defun tile2longitude (x zoom) (- (/ (* x 360) (expt 2 zoom)) 180))

(defun latitude2tile (lat zoom) (* (expt 2 zoom) (/ (- 1 (/ (log (+ (tan (/ (* lat pi) 180)) (/ 1 (cos (/ (* lat pi) 180))))) pi)) 2)))
 
(defun sinh (value) (/ (- (exp value) (exp (- value))) 2))
(defun tile2latitude (y zoom) (/ (* 180 (atan (sinh (* pi (- 1 (* 2 (/ y (expt 2 zoom)))))))) pi))

show

Erlang

-module(slippymap).
-export([deg2num/3]).
-export([num2deg/3]).

deg2num(Lat,Lon,Zoom)->
    X=math:pow(2, Zoom) * ((Lon + 180) / 360),
    Sec=1/math:cos(deg2rad(Lat)),
    R = math:log(math:tan(deg2rad(Lat)) + Sec)/math:pi(),
    Y=math:pow(2, Zoom) * (1 - R) / 2,
    {round(X),round(Y)}.

num2deg(X,Y,Zoom)->
    N=math:pow(2, Zoom),
    Lon=X/N*360-180,
    Lat_rad=math:atan(math:sinh(math:pi()*(1-2*Y/N))),
    Lat=Lat_rad*180/math:pi(),
    {Lon,Lat}.

deg2rad(C)->
    C*math:pi()/180.

show

Lua

function deg2num(lon, lat, zoom)
    local n = 2 ^ zoom
    local lon_deg = tonumber(lon)
    local lat_rad = math.rad(lat)
    local xtile = math.floor(n * ((lon_deg + 180) / 360))
    local ytile = math.floor(n * (1 - (math.log(math.tan(lat_rad) + (1 / math.cos(lat_rad))) / math.pi)) / 2)
    return xtile, ytile
end

function num2deg(x, y, z)
    local n = 2 ^ z
    local lon_deg = x / n * 360.0 - 180.0
    local lat_rad = math.atan(math.sinh(math.pi * (1 - 2 * y / n)))
    local lat_deg = lat_rad * 180.0 / math.pi
    return lon_deg, lat_deg
end

show

PostgreSQL

CREATE OR REPLACE FUNCTION lon2tile(lon DOUBLE PRECISION, zoom INTEGER)
  RETURNS INTEGER AS
$BODY$
    SELECT FLOOR( (lon + 180) / 360 * (1 << zoom) )::INTEGER;
$BODY$
  LANGUAGE SQL COST 1 IMMUTABLE STRICT PARALLEL SAFE;

CREATE OR REPLACE FUNCTION lat2tile(lat DOUBLE PRECISION, zoom INTEGER)
  RETURNS INTEGER AS
$BODY$
    SELECT floor( (1.0 - ln(tan(radians(lat)) + 1.0 / cos(radians(lat))) / pi()) / 2.0 * (1 << zoom) )::INTEGER;
$BODY$
  LANGUAGE SQL COST 1 IMMUTABLE STRICT PARALLEL SAFE;

CREATE OR REPLACE FUNCTION tile2lat(y INTEGER, zoom INTEGER)
  RETURNS double precision AS
$BODY$
DECLARE
 n float;
 sinh float;
 E float = 2.7182818284;
BEGIN
    n = pi() - (2.0 * pi() * y) / power(2.0, zoom);
    sinh = (1 - power(E, -2*n)) / (2 * power(E, -n));
    return degrees(atan(sinh));
END;
$BODY$
  LANGUAGE plpgsql IMMUTABLE;


CREATE OR REPLACE FUNCTION tile2lon(x integer, zoom integer)
  RETURNS double precision AS
$BODY$
 SELECT CAST(x * 1.0 / (1 << zoom) * 360.0 - 180.0 AS double precision);
$BODY$
  LANGUAGE sql IMMUTABLE;

show

Objective-C

+(NSString*) transformWorldCoordinateToTilePathForZoom:(int)zoom fromLon:(double) lon  fromLat:(double) lat
{
    int tileX = (int)(floor((lon + 180.0) / 360.0 * pow(2.0, zoom)));
    int tileY = (int)(floor((1.0 - log( tan(lat * M_PI/180.0) + 1.0 / cos(lat * M_PI/180.0)) / M_PI) / 2.0 * pow(2.0, zoom)));
    NSString * path = [NSString stringWithFormat:@"%d/%d/%d",zoom,tileX,tileY];
    return path;
}

show

Swift

func tranformCoordinate(_ latitude: Double, _ longitude: Double, withZoom zoom: Int) -> (x: Int, y: Int) {
    let tileX = Int(floor((longitude + 180) / 360.0 * pow(2.0, Double(zoom))))
    let tileY = Int(floor((1 - log( tan( latitude * Double.pi / 180.0 ) + 1 / cos( latitude * Double.pi / 180.0 )) / Double.pi ) / 2 * pow(2.0, Double(zoom))))
    
    return (tileX, tileY)
}

    func tileToLatLon(tileX : Int, tileY : Int, mapZoom: Int) -> (lat_deg : Double, lon_deg : Double) {
        let n : Double = pow(2.0, Double(mapZoom))
        let lon = (Double(tileX) / n) * 360.0 - 180.0
        let lat = atan( sinh (.pi - (Double(tileY) / n) * 2 * Double.pi)) * (180.0 / .pi)
        
        return (lat, lon)
    }

show

Clojure

(defn tile [lat lon zoom]
  (let [zoom-shifted (bit-shift-left 1 zoom)
        lat-radians (Math/toRadians lat)
        xtile (int (Math/floor (* (/ (+ 180 lon) 360) zoom-shifted)))
        ytile (int (Math/floor (* (/ (- 1
                                        (/
                                          (Math/log (+ (Math/tan lat-radians)
                                                       (/ 1 (Math/cos lat-radians))))
                                          Math/PI))
                                     2)
                                  zoom-shifted)))]
    (str zoom
         "/"
         (cond (< xtile 0) 0
               (>= xtile zoom-shifted) (- zoom-shifted 1)
               :else xtile)
         "/"
         (cond (< ytile 0) 0
               (>= ytile zoom-shifted) (- zoom-shifted 1)
               :else ytile))))

show

Julia

lng2tile(lng, zoom) = floor((lng+180)/360*2^zoom)
lat2tile(lat, zoom) = floor((1-log(tan(lat*pi/180)+1/cos(lat*pi/180))/pi)/2*2^zoom)

tile2lng(x, z) = (x/2^z*360)-180
tile2lat(y, z) = 180/pi*atan(0.5*(exp(pi-2*pi*y/2^z)-exp(2*pi*y/2^z-pi)))

show

Rust

use std::f64::consts::PI;
fn get_tiles(lat_deg: f64, lon_deg: f64, zoom: i32) -> (i32, i32) {
    let n = (1 << zoom) as f64;

    let x_tile = (n * (lon_deg + 180.0) / 360.0) as i32;

    let lat_rad = lat_deg.to_radians();
    let y_tile = (n * (1.0 - (lat_rad.tan() + (1.0 / lat_rad.cos())).ln() / PI) / 2.0) as i32;

    (x_tile, y_tile)
}

Subtiles

If you're looking at tile x,y and want to zoom in, the subtiles are (in the next zoom-level's coordinate system):

2x, 2y	2x + 1, 2y
2x, 2y + 1	2x + 1, 2y + 1

Similarly, zoom out by halving x and y (in the previous zoom level)

Resolution and Scale

Exact length of the equator (according to Wikipedia) is 40075.016686 km in WGS-84. At zoom 0, one pixel would equal 156543.03 meters (assuming a tile size of 256 px):

40075.016686 * 1000 / 256 ≈ 6378137.0 * 2 * pi / 256 ≈ 156543.03

Which gives us a formula to calculate resolution at any given zoom:

resolution = 156543.03 meters/pixel * cos(latitude) / (2 ^ zoomlevel)

Some applications need to know a map scale, that is, how 1 cm on a screen translates to 1 cm of a map.

scale = 1 : (screen_dpi * 1/0.0254 in/m * resolution)

And here is the table to rid you of those calculations. All values are shown for equator, and you have to multiply them by cos(latitude) to adjust to a given latitude. For example, divide those by 2 for latitude 60 (Oslo, Helsinki, Saint-Petersburg).

zoom	resolution, m/px	scale 90 dpi	1 screen cm is	scale 96 dpi	scale 120 dpi
0	156543.03	1 : 554 680 041	5547 km	1 : 591 658 711	1 : 739 573 389
1	78271.52	1 : 277 340 021	2773 km	1 : 295 829 355	1 : 369 786 694
2	39135.76	1 : 138 670 010	1387 km	1 : 147 914 678	1 : 184 893 347
3	19567.88	1 : 69 335 005	693 km	1 : 73 957 339	1 : 92 446 674
4	9783.94	1 : 34 667 503	347 km	1 : 36 978 669	1 : 46 223 337
5	4891.97	1 : 17 333 751	173 km	1 : 18 489 335	1 : 23 111 668
6	2445.98	1 : 8 666 876	86.7 km	1 : 9 244 667	1 : 11 555 834
7	1222.99	1 : 4 333 438	43.3 km	1 : 4 622 334	1 : 5 777 917
8	611.50	1 : 2 166 719	21.7 km	1 : 2 311 167	1 : 2 888 959
9	305.75	1 : 1 083 359	10.8 km	1 : 1 155 583	1 : 1 444 479
10	152.87	1 : 541 680	5.4 km	1 : 577 792	1 : 722 240
11	76.437	1 : 270 840	2.7 km	1 : 288 896	1 : 361 120
12	38.219	1 : 135 420	1.35 km	1 : 144 448	1 : 180 560
13	19.109	1 : 67 710	677 m	1 : 72 224	1 : 90 280
14	9.5546	1 : 33 855	339 m	1 : 36 112	1 : 45 140
15	4.7773	1 : 16 927	169 m	1 : 18 056	1 : 22 570
16	2.3887	1 : 8 464	84.6 m	1 : 9 028	1 : 11 285
17	1.1943	1 : 4 232	42.3 m	1 : 4 514	1 : 5 642
18	0.5972	1 : 2 116	21.2 m	1 : 2 257	1 : 2 821

See also Zoom levels

Tools

• Geo-OSM-Tiles: a Perl module that calculates tile numbers along with a script that downloads map tiles
• Kachelbrowser
• File:Lat lon.odt feuille de calcul openoffice (sheet)
• Geofabrik map showing tile grid and coordinates on the map
• What the Quad - Get the z/x/y tile coordinate for any place on the map by just clicking on it. Also provides Bing Quadkey and lon/lat coordinates.

References

• http://cfis.savagexi.com/articles/2006/05/03/google-maps-deconstructed
• Setting up TMS
• TMS specification from the OSGeo Foundation

(note: Slippy tiles and Google map tiles count tile 0,0 down from the top-left of the tile grid; the TMS spec specifies tiles count up from 0,0 in the lower-left!)