Enter the total rise between floors to get the number of steps, the riser height and the total run.
What this calculator does
This stair calculator sizes a staircase from the total floor-to-floor height. It divides the rise into comfortable steps, gives the exact riser height, and works out the total horizontal run from your tread depth.
It’s a planning aid — always check local building codes for riser and tread limits.
Step by step
- Enter the total rise (floor to floor) in inches.
- Set a target riser height and tread depth.
- Read the number of steps, riser height and run.
The maths behind it
steps = round(total rise ÷ target riser)
riser = total rise ÷ steps · run = (steps − 1) × tread
The default scenario, worked through
As an example, with a total rise of 108, the calculator returns a number of steps of 14. Underneath, Riser height comes out at 7.71 in and Number of treads at 13. Change any field and every figure updates as you type.
Frequently asked questions
What’s a comfortable riser height?
Around 7 to 7.75 inches is typical and common in codes. This tool aims for your target and evens it out across the steps.
How deep should treads be?
About 10–11 inches is comfortable; codes often set a minimum around 10 inches.
Are these code-compliant?
It’s an estimate. Building codes vary, so confirm riser and tread limits locally before building.