Example: Total rise (floor to floor): 108 in · Target riser height: 7.5 in · Tread depth: 10.5 in → Number of risers: 14.
Actual riser height: 7.71 in
Treads: 13
Total run: 11.38 ft
Frequently asked questions
How do I calculate stair? Enter your numbers above and the result updates instantly. For example: Total rise (floor to floor): 108 in · Target riser height: 7.5 in · Tread depth: 10.5 in → Number of risers: 14.
Is this Stair Calculator free? Yes — completely free with no sign-up or paywall. It runs entirely in your browser and keeps working offline; the numbers you enter never leave your device.
How accurate is it? It uses the standard published formula for stair. Results are estimates for planning — not financial, tax, medical, engineering, or legal advice.