Stair Calculator
Plan a basic straight stair by estimating riser count and tread run.
Project details
Estimate
Planning estimate only. Verify product dimensions, manufacturer coverage, local requirements and field conditions before purchasing.
How the stair estimate works
Total rise is divided by the target riser height and rounded to a practical riser count. The actual riser height is recalculated from that count. For a basic straight stair, tread count is one less than riser count.
This is a planning calculator only. Stair geometry is safety-critical and must comply with applicable building codes and site conditions.
Stair Calculator FAQ
Can I build stairs directly from this result?
No. Verify all dimensions against applicable code and actual site conditions before construction.
Why are treads one less than risers?
In a basic floor-to-floor stair, the upper floor commonly serves as the final landing rather than a separate tread.
Does this calculate stringer cuts?
No. Stringer layout and structural details require additional design checks.