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Public-images-osm logo.svg maxweight
Zeichen 262.svg
Permissible maximum actual weight in metric tonnes (or other explicitly specified unit). Show/edit corresponding data item.
Group: restrictions
Used on these elements
may be used on nodesmay be used on waysmay be used on areas (and multipolygon relations)may be used on relations
Useful combination
See also
Status: de factoPage for proposal

Legal access restriction for vehicles or passengers that exceed the specified actual weight, especially useful on bridge segments (tagged with bridge=*). Metric tonnes are a default unit, other units must be explicitly tagged. Typical usage is to add this tag to highway=* lines where maxweight limit applies.

Note: for maximum gross weight see maxweightrating=*

Vehicle weight

A number of navigable structures that are mapped as ways or areas may be tagged with a vehicle weight restriction, such as:

If a unit is not specified, the value is assumed to be in tonnes (British English, 'metric tons' in American English). You must explicitly specify the unit if it is not in metric tonnes. See page Units for possible units and format. If the restriction applies only to some classes of vehicles, way direction, lanes, or time condition, follow maxspeed#Extended tagging.

In cases of some objects, for example bridges it may be desirable to tag that place was surveyed and no max weight sign was found. Tag used for this include maxweight=unsigned and maxweight:signed=no. There is also maxweight=none, but it is misleading as there are also default max weight of vehicles set by law, it is unlikely to find place where one is actually allowed to drive vehicles without any weight limits. However, it is the value used with maxweight:conditional=none @ * so should be treated as meaning defaults apply.

Basic example

bridge from the given example

A small bridge with limited weight

Tags on a road segment representing road on a bridge:

Regional variations

Vienna Convention

In the Vienna Convention on Road Traffic (Nov 8, 1968), this property relates to Chapter 1, Art. 1 (y) Laden mass means the actual mass of the vehicle as loaded, with the crew and passengers on board;

United States

In most of the United States, weight restrictions are expressed in short tons (abbreviated as "tons", "T", or "t"), which should be tagged as maxweight=### st, and sometimes in pounds (abbreviated as "lbs"), which should be tagged as maxweight=### lbs, but never as metric tons. In Texas, the weight given on signs is always expressed in pounds; likewise in Mississippi, where most weights in pounds do not divide evenly into tons. [2] (In the past, many mappers converted short tons to pounds and used the lbs suffix even when the signs were expressed in short tons. More recently, the st suffix was introduced for short tons, so that mappers don't have to do arithmetic.[1])

Besides the prima facie restrictions on the signs below, each state has a number of statutory tolerances and exemptions for specific types of cargo, often seasonally.[2] Mappers should focus on the restrictions on the signs and ignore statutory exceptions.

New Zealand

Bridge weight restrictions in New Zealand are usually expressed either as a percentage of Class 1 (or Class I) standard or General Access standard, as prescribed in the Vehicle Dimensions and Mass rules (this is distinct from the Class 1 "car" driver licence weight limit of 6 tonnes.) As the percentage signs require a bit of knowledge of the VDAM rules and some arithmetic, they are slowly being phased out with signage showing the maximum weight based on the number of axles.

The Class 1 standard is as follows:

  • 2 axles = 15.5 tonnes
  • 3 axles = 22 tonnes
  • 4 axles = 26 tonnes
  • 5 axles = 32 tonnes
  • 6 axles = 36 tonnes
  • 7 axles = 40 tonnes
  • 8 or more axles = 44 tonnes

Examples by sign

with signs around the world:


United States

Federal, state, county, and municipal highway departments post a wide variety of sign designs that indicate a number of different formulae for computing weight restrictions. The most common sign designs are displayed in the following gallery, most of them from state standards.


Caution, pitfall! The signs below are not weight restrictions, but rather restrictions for goods vehicles with a maximum allowed weight above the depicted value, or max weight per axle not per vehicle.

See more examples at Key:maxweightrating and Key:maxaxleload pages.

Passenger weight

This key is also used to indicate a maximum passenger weight on some conveyances that may be mapped as nodes, ways, or areas, such as:

These restrictions are usually expressed in human-scale units, such as kilograms (kg) and pounds (lbs). You must explicitly specify the unit to prevent data consumers from misinterpreting a passenger weight restriction as a tonnage.


  2. “Compilation of Existing State Truck Size and Weight Limit Laws”. Federal Highway Administration. February 1, 2017. Retrieved July 6, 2019. 
  3. Each Class I weight for an axle configuration is multiplied by 0.7. For 2-axle and 3-axle vehicles, the maximum axle load (4600 kg) limits the gross weight further below 70% of Class I.
  4. Per section 2B.64 of the MUTCD: "The symbols shown on the R12-5 and R12-6 Weight Limit sign [single-unit truck single-trailer multi-trailer] shall apply to all trucks of that configuration (single-unit, single-trailer or multi-trailer) regardless of the shape of the vehicle." [1]
  5. “Weight Limit Signs”. Marshall, Michigan: Calhoun County Road Department. 2015. Archived from the original on July 3, 2015. 
  6. proposed on tagging mailing list as maxemptyweight=*, later changed proposed key for reasons listed in

See also

  • maxweightrating=* - for restrictions that are not based on the actual weight but on the gross maximal mass rating of the vehicle. (Legal access restriction for vehicles with a maximum permitted mass above the specified mass in metric tonnes).
  • maxaxleload=* - The legal maximum axleload in metric tonnes.
  • access=* - legal accessibility according to vehicle class or kind of use
  • amenity=weighbridge - A large weight scale to weigh vehicles and goods
  • Conditional restrictions - restrictions depending on a condition.
  • Proposed_features/gross_weight - Proposal to express limitations/restrictions of the acutal weight, weight rating of vehicles and combinations (trailers) and to express conditional restrictions based on weight properties
  • Relation:enforcement + enforcement=maxweight - permanently installed devices that measure and document traffic violations, such as maxweight

External links

  • "Vehicle Types", Traffic Monitoring Guide, U.S. Federal Highway Administration Office of Highway Policy Information – helpful for interpreting truck symbols on U.S. signs