Stair Stringer Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
100% FreeRuns in your browserBasic
Enter Values
Enter your values and press Calculate to see results.
How to use this calculator
- Enter the total rise (floor to floor) and your preferred riser height.
- Optionally add the total run for the tread depth.
How it works
Steps = total rise ÷ preferred riser, rounded to a whole number; the actual riser is the total rise ÷ steps.
Worked example
2700 mm rise, 180 mm target. 15 risers at 180 mm, 14 treads.
Common mistakes
- Uneven last step — all risers must be equal, so the actual riser rarely equals your target exactly.
- Ignoring code limits on riser height and tread depth.
Frequently asked questions
Is this code-compliant?
It's a planning aid only — always check riser/tread limits in your local building code before building.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.