DIY & materials
Stair rise and going Calculator
Explore riser count, stair run, angle and footprint. This free stair rise and going calculator shows the calculation and its assumptions so you can compare your own figures.
Your results
Explore riser count, stair run, angle and footprint.
Calculated outcomes
- Treads
- 15
- Total Run MM
- 3,750 mm
- Pitch Degrees
- 34.99 °
- Comfort Sum MM
- 600 mm
- Stair Footprint M2
- 3.375 m²
Assumptions and estimates
- Method: Risers = ceiling(total rise ÷ target riser), with at least two. Treads = risers − 1; comfort expression = 2 × rise + going.
- Geometry only. The comfort expression is not an Irish compliance check. Headroom, landings, guarding, accessibility and applicable building rules require design review.
Useful next steps
- Use Compare options to test an alternative side by side.
- Copy, print or download a record of this calculation when you need one.
Reports open your email app addressed to s@s1.ie with the public page address only. Your inputs are never added.
How the stair rise and going calculation works
Risers = ceiling(total rise ÷ target riser), with at least two. Treads = risers − 1; comfort expression = 2 × rise + going.
Geometry only. The comfort expression is not an Irish compliance check. Headroom, landings, guarding, accessibility and applicable building rules require design review.
Using this calculator
- Enter your own figures in the labelled inputs. Keep the currencies, units and time periods consistent.
- Choose any applicable rate profile, pattern or assumption shown for this tool. Open additional inputs when relevant.
- Review risers and actual riser mm, then read the stated assumptions and eligibility conditions before using the result.
Worked example
This is a static example using illustrative inputs, not facts about you or today’s date. The displayed eligibility selections and assumptions apply only to this example.
See example inputs
- Floor-to-floor rise (mm)
- 2800
- Target maximum riser (mm)
- 180
- Tread going (mm)
- 250
- Stair width (mm)
- 900
- Risers
- 16
- Actual Riser MM
- 175 mm