Talk:Zoom levels

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Why are the decimal values listed with . and , on a single zoom table? (Yosun 09:55, 24 February 2012 (UTC))

"," is thousand separator, "." is decimal separator. 123456/10 can be written: 12,345.6 Still I agree, decimal should be there also for large numbers. Ideally there should be a discussion on the units per pixel you find in configuration files for tile services. Mayeul 21:39, 25 February 2012 (UTC)

With an error of more than one permille in the very shape of the Earth, there is little sense anyway in giving the numbers with more than four significant digits ...--hagman (talk) 11:16, 11 December 2016 (UTC)

Add more levels past 19

Please continue the chart. On http://www.openstreetmap.org/ the Humanitarian Layer and ID already go beyond this. Jidanni (talk) 03:38, 9 November 2017 (UTC)

m / pixel is not very precise

For example for zoom 13 it should be (6378137 * pi * 2) / (2 ^ 13) / 256 = 19.1092570713 but listed value is 19.093.

--*Martin* (talk) 13:00, 27 June 2020 (UTC)

Because earth isn't a perfect sphere, the  Earth radius isn't constant.

Its value ranges from 6,378 km (3,963 mi) at the equator to 6,357 km (3,950 mi) at a pole.

The resulting value according the formula above should thus range from ~19.04592943083793 m/pixel and ~19.108846611591055 m/pixel. 19.093 thus seems like a good compromise that doesn't suggest a much higher precision than there can physically be. (One could argue that it even still suggests too much precision.)
Note that the values given in this article aren't meant as base for precise geographical computation, but rather to give a rough "feeling" for the scope and range of the zoom levels. --Das-g (talk) 13:34, 27 June 2020 (UTC)
Thanks for the explanation. My computed value is for pseudomercator (EPSG:3857) projection which is commonly used for OpenStreetMap raster maps. --*Martin* (talk) 13:39, 27 June 2020 (UTC)

Higher zoom

People often ask for higher zoom levels, especially for vector renderers, so here they are, unless I miscalculated. ;-)

zoom level length/pixel
21 5.1 cm
22 2.5 cm
23 1.3 cm
24 6.4 mm

--grin 07:33, 7 October 2022 (UTC)