Tool

Stair runner length calculator app

There is no app store download here — and there does not need to be. The calculator is a web page that behaves like an app on a phone: large fields, instant recalculation, and a results panel that stays readable one-handed.

Add it to your home screen and it opens full screen like any other app.

Your staircase

Start from typical stair sizes where you live

IRC-style stairs: 10 in minimum tread, 7¾ in maximum riser. Runners are usually 27 in or 32 in wide and sold by the linear foot.

Number of stairs

Count every step you will cover.

Tread depth (in)

Front edge to back of the step. Fractions like 10 1/2 work.

Riser height (in)

The vertical face between two treads.

Waste allowance

Custom%

10% is a common starting point; pattern matching and winders need more.

Add a nosing / overhang allowance per step

Needed when the runner wraps around a projecting nose (Hollywood installs and thick pads). Waterfall installs usually don't need it.

Your stair runner length

20 ft 3.1 in

Total runner required for 13 steps, including a 10% waste allowance.

Total runner length in each unit
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

Side elevation of a staircase. The runner travels across each tread and down each riser, so every step consumes tread depth plus riser height of material.

Add to home screen

On iPhone, tap Share then 'Add to Home Screen'. On Android, open the browser menu and choose 'Add to Home screen' or 'Install'. It then launches from an icon like a native app.

Designed for on-site use

Fields accept fractions so you can type what the tape says. Nothing is submitted, so there is no waiting on a connection in a stairwell. Saved staircases persist between visits.

Why not a native app

A native app would need updating, permissions and an account. A web page needs none of those and gives you exactly the same arithmetic on every device.

Questions people ask

Is there a stair runner calculator app to download?: You do not need one. Add this page to your phone's home screen and it opens full screen with all the same features offline once loaded.
Do saved staircases sync between devices?: No. They are stored privately in the browser you saved them in. Use the share link to move a calculation to another device.

Related guides

See all stair runner calculator guides