About Stair Calculator
Calculate stair stringer rise, run, tread count, and angle according to IRC building code.. Designed for accurate, instantaneous calculations with zero wait time.
Formula
Number of Risers = Total Rise / 7.75" | Exact Rise = Total Rise / Number of Risers
Example Calculation
A total rise of 105 inches requires 14 risers at 7.50 inches each with 13 treads.
How to Use
- Enter your values into the form fields above.
- The calculation updates immediately in real time.
- Inspect the main summary and secondary breakdowns below.