Part of the topic: 🏠 Home, energy & car
Stair calculator (DIN 18065)
Enter the finished floor-to-floor height and your preferred riser height. The calculator rounds to whole steps and applies the step rule 2 risers + 1 tread ≈ 63 cm.
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How to use it
- Measure the finished floor-to-floor height (top of finished floor to top of finished floor).
- Enter a preferred riser height – 17–18 cm is comfortable.
- Check risers, tread depth, run length and the DIN ranges.
Last checked: October 2026 · Based on: DIN 18065 (stairs in buildings): riser/tread ranges, step rule 59–65 cm. Found a mistake? Use the form below – we fix confirmed errors and update the date.
Frequently asked questions
What is the step rule for stairs?
2 × riser + tread = 59 to 65 cm, ideally about 63 cm (average human stride).
How many steps for 280 cm floor height?
With about 17.5 cm risers: 16 risers of 17.5 cm and 15 treads of about 28 cm.
What is the maximum riser height in a house?
For necessary stairs in residential buildings with up to two dwellings DIN 18065 allows up to 20 cm; 17–18 cm is more comfortable.