Stair Stringer Calculator
Calculate stair riser count, actual riser height, tread layout and overall run from a measured total rise.
Results
Risers
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Treads
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Actual riser height
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Total horizontal run
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Stair angle
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Approx. stringer slope length
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Use the result as a planning estimate and verify project-specific measurements, manufacturer information and local requirements where relevant.
How it works
The calculator rounds the number of risers up so the actual riser height does not exceed the entered target, then uses one fewer tread than risers for a floor-to-floor layout.
risers = ceil(total rise ÷ target riser); actual rise = total rise ÷ risersLimitations
- Stair rules vary by jurisdiction and situation. Verify riser/tread limits, landings, headroom, nosing and guard/handrail requirements independently.
- The stringer result is geometric only and does not size or certify the structural member.