From OpenStreetMap Wiki
Jump to: navigation, search
Available languages — Key:smoothness
Public-images-osm logo.svg smoothness
Jena Track roots.jpg
Provide a classification scheme regarding the physical usability of a way for wheeled vehicles.
Group: Properties
Used on these elements
should not be used on nodesmay be used on waysmay be used on areasuse on relations unspecified
Useful combination
Status: ApprovedPage for proposal

smoothness provides a classification scheme regarding the physical usability of a way for wheeled vehicles, particularly regarding surface regularity/flatness. Usability by a particular type of vehicle means that the vehicle can traverse the route without significant risk of damage (e.g., to vehicle undercarriage/drivetrain) or injury (e.g., by falling). The tag can be applied to all driveable ways and areas: highway=*, parking areas, beaches, etc.

tracktype=* is also an important surface property and refers to surface firmness, regardless of shape.

surface=* refers to surface material and sometimes to material structure. It may suggest a surface smoothness sometimes, but because the same surface material/structure can exhibit various shapes, it is still advisable to add smoothness=*.



Key Value Element Usable by Rendering Photo
smoothness excellent Way Area (thin_rollers) roller blade, skate board and all below Highway secondary-photo.jpg
smoothness good Way Area (thin_wheels) racing bike and all below Bus prumyslova.jpg
smoothness intermediate Way Area (wheels) city bike, sport cars, wheel chair, Scooter and all below Map feature ford.jpg
smoothness bad Way Area (robust_wheels) trekking bike, normal cars, Rickshaw and all below Smoothnessverybad.jpg
smoothness very_bad Way Area (high_clearance) Car with high clearance, light-duty off road vehicles Mountain-track1.jpg
smoothness horrible Way Area (off_road_wheels) heavy-duty off road vehicles and all below Jena Trackexample profile.jpg
smoothness very_horrible Way Area (specialized_off_road_wheels) tractor, ATV, tanks, trial, Mountain bike and all kind of off-highway vehicles (see also mtb:scale=*) Mountain-track5.jpg
smoothness impassable Way Area No wheeled vehicle (see also sac_scale=*) Smoothness impassable.JPG

Please note: Photos are examples ONLY ! Because the smoothness of a way should be assessed solely based on whether the way is usable by the vehicles mentioned above. This is my whole point: as a user of a certain road or path I am only interested whether I can drive on this road or not.

This table is a wiki template with a default description in English. Editable here.


This tag isn't in use on the renderers at, but Hiking/openhikingmap and the Motorcycle map of Romania are using "surface" and "smoothness" to depict real state of roads.

In developing countries, the HDM model is using some values of smoothness=* to help define road quality.


It is clear from discussion on the mailing lists that a major part of the community does not like this key, based on the guideline of Verifiability. Please have a look at the discussion page and the mailing-list (thread starting at [1], contiued at [2]) and make up your own mind. As always on OSM you are free to use the keys you like in the way you like! Use the page Talk:Proposed features/Smoothness for the controversy details. Please help improving the tagging of roads by posting constructive comments to Proposed_features/surface_unification.

  • The key could be made more verifiable changing the values to thin_rollers, thin_wheels, wheels, robust_wheels, high_clearance, off_road_wheels and specialized_off_road_wheels. (See Proposed_features/usability) for a transition.)

See also