How can I get road width data from OSM?

[aditaMou (Adita Sen)]

Hello OSM Team,

I am working on a research project at University of Bremen, Germany, and we need accurate road width information for analysis. While OSM provides excellent road geometry and length data, width tags are often missing.

I have also noticed that sometimes we assume default width values (for example, setting a standard width of 5–6 m for residential roads without field measurements). Could you please clarify:

1. How reliable are these default width values?
2. Is there a recommended approach to distinguish between measured widths and estimated/default widths in OSM data?
3. Whether there is any existing dataset or extract that includes road width information.
4. Are there recommended tools or approaches to estimate width from existing attributes (e.g., number of lanes or highway type)?

We highly appreciate the efforts of the OSM community and would be glad to contribute back if possible.

Thank you very much for your time and support.

Kind regards,
Adita Sen
Student Assistant
University of Bremen, Germany

[ImreSamu]

@aditaMou

and we need accurate road width information for analysis.

maybe related:

Check the “a/b-street” project

• Intersection geometry - A/B Street ( search: “width” )

• The State of the Map talk: slides, video (August 2022)

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In Africa, highway tagging differs from Europe’s ( see the pictures )

• East Africa Tagging Guidelines - OpenStreetMap Wiki
• Highway Tag Africa - OpenStreetMap Wiki

[SomeoneElse (Andy Townsend)]

@aditaMou

for example, setting a standard width of 5–6 m for residential roads without field measurements

@aditaMou

How reliable are these default width values?

In order to see how actual values in OSM compare with any default you can look at taginfo for the whole world or just for Germany (that may take a while to appear). That’s the width for “absolutely anything”, but most widths are on highways and most highways are roads.

You can also use overpass.

In the UK I don’t think that most highway=residential roads are 5 or 6m wide, but that might be different in your area of interest. It will obviously vary hugely around the world.

[Vinzenz_Mai]

@aditaMou , willkommen hier im Forum.

@aditaMou

How reliable are these default width values?

Not too much, please read Schmale Straßen und Graphhopper (Tausende Routingfehler in D)

@Mammi71

@Luzandro

Ich glaube das war ein Bug im iD-Editor, wenn man “0,x” statt “0.x” eingegeben hat, wurde das kommentarlos zu “0” verkürzt

Das würde auch die vielen “2” erklären, die eigentlich “2.x” sein sollten. Jedoch erklärt dies nicht die “2” an residential und höher, wo nachgemessen eher >4m breit sind.

@aditaMou

Is there a recommended approach to distinguish between measured widths and estimated/default widths in OSM data?

No, there’s only the value “width”, not how the mapper got that value.
Only yesterday I added a newly constructed road segment, width of the road measured by a smartphone app, width of the new cycleway measured by my shoes. Second one is a reliable value

@aditaMou

Are there recommended tools or approaches to estimate width from existing attributes (e.g., number of lanes or highway type)?

Even with the same highway type there may be great differences in width:
Examples of highway=scondary in the same federal state of Germany

L 102 at Riesweiler

Way: ‪L 102‬ (‪33840449‬)

Mapillary

Way: ‪L 254‬ (‪376653666‬)

Mapillary

I did move the second one from tertiary to secondary some years ago but I hadn’t the courage to downgrade L 102 from secondary to tertiary.