construction calculator
Stair Rise & Run Calculator
Lay out a stair: number of risers, actual riser height, tread count, and total run from the total rise.
How it works
Risers = round(total rise / target riser). Actual riser = total rise / risers. Run = (risers - 1) x tread depth.
Worked example
A 105 in total rise at a 7 in target: 15 risers at 7.00 in, 14 treads, 140 in of run.
When to use it
- IRC limits: maximum riser 7 3/4 in, minimum tread depth 10 in.
- Confirm the actual riser height stays within your local code.
Related calculators
All results are an engineering estimate — not for custody transfer. Field measurement and certified tables govern.