MileCheckWhat is WZDx work zone data?
WZDx, the Work Zone Data Exchange, is a standard format for publishing work zones. It was set up with the US Department of Transportation. A WZDx feed is a GeoJSON file listing each work zone with its road, direction, location, dates and lane impact.
What's in a feed
- The road name and direction.
- The start and end of the work zone, as a line or points.
- Start and end dates.
- The impact on traffic, such as some lanes or all lanes closed.
- A description, and who published it.
Coordinates are GeoJSON, longitude first.
Version and registry
USDOT lists version 4.2, released in February 2023, as the latest. Active feeds are listed in the WZDx Feed Registry (USDOT WZDx page, checked November 5, 2026).
The catch
A feed can follow the format and still differ. Some publish highway names instead of route numbers. Some list local streets next to interstates. Some update weekly. You still have to check each one.
How MileCheck uses it
MileCheck reads WZDx feeds for New Jersey, New Mexico and Hawaii, alongside each other state's own format. The MileCheck API returns all of them in one shape.
Live state DOT feeds in one format
Closures, crashes, construction, chain controls, drawbridges and border waits, plus GPS to mile marker. The test key is instant, with no email.
Questions, answered
Does every state publish WZDx?
No. Many publish work zones only in their own 511 format.
Is WZDx data free to use?
Each publisher sets its terms. Some feeds are public domain. Read each feed's license.