U.S. speed limits
The highest posted limit in every state and county, by road class. Pick a road class, then click a state to see its counties.
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United States
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About the data
- Each county shows the highest posted limit on that road class within it, from the FHWA Highway Performance Monitoring System (HPMS) 2024, the road inventory every state DOT submits. About 190 gaps are filled from OpenStreetMap.
- Values above a state's legal maximum were kept only where OpenStreetMap showed the same posting.
- Striped counties have the road class but no reported limit, so the state default is shown.
- Updated for 2025–26 law changes: Iowa two-lane roads 60 mph, North Dakota Interstates 80 mph. Missouri's 75 mph law is not yet posted, so it still shows 70.
- A state's value is its highest county posting. Posted limits change; check the signs.