Stair Runner Length CalculatorMeasurement
Stair runner length calculator by tread and riser
Tread depth and riser height are the two measurements that decide everything. Get them right and the rest of the calculation is arithmetic.
Tread depth is the horizontal surface you walk on, measured from the face of one riser to the front edge of the nosing. Riser height is the vertical face between two treads.
Stair runner calculator
Your stair runner length
20 ft 3.1 in
Total runner required for 13 steps, including a 10% waste allowance.
| Inches | 243.1 in |
|---|---|
| Feet | 20.26 ft |
| Feet & inches | 20 ft 3.1 in |
| Yards | 6.75 yd |
| Meters | 6.17 m |
| Centimeters | 617.47 cm |
Recommended purchase length
21 ft
7 yd · 6.4 m · 252 in
This calculator provides an estimate based on the measurements and installation assumptions you enter. Complex, curved or winder staircases may require professional measurement.
Your measurements, drawn to scale
Measuring the tread
Include the nosing overhang if the runner will wrap over it. Measure at the centre of the step, and check three separate steps — older stairs are rarely uniform.
Measuring the riser
Measure from the top of one tread to the top of the next, at the front. On carpeted stairs, measure to the timber, not to the existing carpet surface.
When the steps are not equal
Use the largest tread and largest riser you find rather than an average. Being half an inch long on every step costs you a few inches of offcut; being half an inch short costs you the whole runner.
Questions people ask
- Should tread depth include the nosing?
- Yes if the runner wraps over the nosing, which it normally does. Measure to the front edge of the overhang.
- What if my steps are different sizes?
- Measure several and use the largest values. Enter the bottom step separately if it is a bullnose or curtail step.