Stair Calculator
About Our Stair Calculator
Building stairs is not simple – you must get every measurement correct. Riser height, tread depth, number of steps, total run and slope angle all need to be perfect for comfort and safety.
That’s why we created our Stair Calculator. Just enter your floor height and preferred riser or tread size. Our tool instantly calculates:
✔ Number of steps
✔ Riser height
✔ Tread depth
✔ Total run
✔ Stair angle
✔ Stringer length
Perfect for contractors, carpenters, designers and DIY homeowners.
Why Use Our Stair Calculator?
- Extremely accurate stair layout generator
- Ideal for wooden, concrete, metal or prefab stairs
- Helps follow building standards
- Prevents uneven steps (safety risk)
- Perfect for renovation and new construction
- Fast, simple and 100% free
- Includes a full summary you can save or export
We built it to remove the confusion from stair planning.
How To Use Our Tool?
- Enter total floor height
- Enter preferred riser height OR let the tool auto-calculate
- Enter desired tread depth
- Click Calculate
You will get:
✔ Step count
✔ Actual riser height
✔ Actual tread depth
✔ Total run (horizontal length)
✔ Stair angle
✔ Stringer length
✔ Easy-to-read summary
Tips (Short, clear, real construction advice)
- Comfortable riser height: 160–180 mm
- Comfortable tread depth: 260–300 mm
- Stair angle should be 30°–38°
- Avoid riser height differences between steps
- Use a landing if total run is too long
- For outdoor stairs → use deeper treads
- Double-check floor height before calculating
Benefits:
- Perfect stair layout in seconds
- Saves time on site measurement
- Helps reduce mistakes
- Good for both homeowners & professionals
- Supports any type of staircase
- Free, clean and simple to use
FAQs:
1. What is the standard riser height?
Most comfortable riser height is around 170 mm.
2. What is a good stair angle?
Between 30° to 38° for safe and comfortable stairs.
3. Can this calculator design concrete stairs?
Yes, works for all materials.
4. Can I change tread depth?
Yes – just enter your preferred measurement.
5. Does this include stringer length?
Yes, calculated automatically.
6. Can I use this for spiral stairs?
This tool is for straight stairs only.
7. Is it free?
Yes – free forever.
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