How to use this tool
Enter the total floor-to-floor rise and your chosen minimum and maximum riser heights.
Set the tread going and your minimum going. These are your design limits; the tool does not check local code, headroom or structure.
Risers = ceil(total rise / entered maximum rise); equal riser = total rise / risers
Worked example
16 · equal risers
Fixed example using the settings below. Monetary examples use USD; dates and times use their stated reference values. This example stays unchanged when you edit your calculation.
Example inputs
- Total floor-to-floor rise (mm): 2800
- Your maximum riser height (mm): 180
- Your minimum riser height (mm): 100
- Tread going (mm): 250
- Your minimum going (mm): 250
Method illustration: 2,800 mm with a maximum 180 mm rise needs 16 risers of 175 mm.
Assumptions and limits
- Entered limits are your design assumptions, not a jurisdiction's building code. No compliance, structural or headroom assessment is provided.
- A straight flight uses one fewer tread than risers, assuming the upper floor is the final landing. Landings and nosings are excluded.
Check or report a result
Check the units, selected calculation and assumptions first. Compare the fixed example above with your inputs to identify what changed.
Report a calculation issue with the page address, hypothetical inputs, result displayed and result expected. Do not include passwords, bank details or other private information.