How many stair steps you need
Step count is steps = round(total rise ÷ target riser), then the actual riser = total rise ÷ steps. A 44 in total rise with a 7.5 in target gives 6 steps at 7.33 in each. All risers must be equal. Where the run allows it, a slope instead of steps is sized by the ramp slope calculator.
How to use this calculator
Measure the total rise floor-to-floor in inches and pick a target riser (7–7.75 in is comfortable). The tool rounds to whole steps and recomputes the exact riser. Boards for the treads are sized by the deck boards calculator. Ground fall is measured with the elevation grade calculator.
Code and comfort
Most codes cap risers near 7.75 in and set tread depth around 10–11 in. Equal risers are required so people don't trip. For an outdoor stair on a deck footing, size the pour with the concrete calculator.
Measure the total rise from finished floor to finished floor and include any flooring not yet laid, because half an inch of tile at the top changes every riser. The upper floor is the last step, so a flight with six risers has five treads. Check headroom too, keeping roughly 6 ft 8 in of clearance measured vertically from the nosing line, and make sure the floor opening is long enough for the run the step count produces.
Frequently asked questions
- How do I calculate stair steps?
- Divide the total rise by your target riser height and round to the nearest whole number of steps.
- What is a comfortable riser height?
- About 7 to 7.75 inches per step is comfortable and meets most building codes.
- Why must all risers be equal?
- Uneven risers are a trip hazard and are not allowed by code, so the riser is divided evenly.
- What tread depth should I use?
- Typically 10–11 inches deep so the foot lands fully on each step.
- Is there a rule of thumb for riser and tread together?
- Yes: twice the riser plus the tread should land near 25 inches. A 7.33 inch riser suits a tread of about 10.3 inches, which is why comfortable stairs cluster around 7 by 11.