Designing a staircase? Our free Stair Calculator turns your floor-to-floor height into the ideal number of risers, even riser heights and total run — for a comfortable stair that meets typical building guidance.
Stair angle: 0° (30–37° is generally comfortable). Always check local building regulations for maximum riser and minimum going. Everything runs in your browser; nothing is uploaded.
How to Use
- Measure the total rise — the vertical distance from the lower floor to the upper floor — in centimetres.
- Enter your desired riser height (around 17–18 cm is comfortable).
- Enter your tread depth, or going (25–30 cm suits most homes).
- Click Calculate to see the riser count, even riser height and total run.
- Check the stair angle and adjust your inputs until it sits in the comfortable range.
Key Features
- Optimal riser count from your floor-to-floor height.
- Even riser height so every step feels the same.
- Tread count and total horizontal run.
- Stair angle with a comfort-range guide.
- 100% private — all calculations happen in your browser.
FAQs
What is the ideal stair riser height?
Between 17 and 18 cm is comfortable for most people. Building regulations in many regions cap risers at around 19–20 cm — always verify locally.
What tread depth should I use?
25 to 30 cm suits most homes. Deeper treads feel safer and more comfortable, especially on the main staircase.
How do I measure the total rise?
Measure vertically from the finished surface of the lower floor to the finished surface of the upper floor, including any floor coverings.
Why must all risers be equal?
Even a small variation trips people up, because we climb stairs on muscle memory. Building codes require riser heights to be uniform within a flight.
Is my project data sent anywhere?
No. The calculator runs entirely in your browser with JavaScript, so your measurements never leave your device.
Related Tools
You may also like our Flooring Calculator, Area Calculator and Volume Calculator.