Width tool
Stair Runner Width Calculator
Measure your stairs once and see instantly which standard stair runner width fits — and exactly how much bare stair each option leaves on show.
Recommended: 27in (70cm) or 30in (76cm)
Aim for 3–4in (7.5–10cm) of bare stair showing each side of the runner.
| Runner width | Reveal each side | Verdict |
|---|---|---|
| 18in / 45cm | 9.0in / 22.9cm | Narrow-looking |
| 20in / 50cm | 8.0in / 20.3cm | Narrow-looking |
| 22in / 55cm | 7.0in / 17.8cm | Narrow-looking |
| 24in / 60cm | 6.0in / 15.2cm | Narrow-looking |
| 27in / 70cm | 4.5in / 11.4cm | Ideal |
| 30in / 76cm | 3.0in / 7.6cm | Ideal |
| 32in / 80cm | 2.0in / 5.1cm | Workable |
| 36in / 90cm | 0.0in / 0.0cm | Too wide |
| 39in / 100cm | — | Too wide |
| 42in / 107cm | — | Too wide |
| 48in / 120cm | — | Too wide |
| 54in / 137cm | — | Too wide |
| 60in / 152cm | — | Too wide |
Turn the width calculator into a client-ready quote
Everything on this page is free and needs no account. If you fit stairs for a living, Riser takes the same numbers and turns them into saved projects, branded quotes, invoices and a client portal.
- Compares every stock width against your staircase at once
- Exact reveal left on each side, in inches or centimetres
- Flags when a custom cut-and-bind width is the better answer
- Saves widths onto projects and client quotes
The free stair runner calculator and every tool on this site stay open to everyone.
Quick answer
What width stair runner do I need?
Most staircases take a 27in (70cm) stair runner. Measure the tread from wall to wall or between the skirting and the outer edge, then subtract 6-8in so 3-4in of stair shows each side. A 33in staircase suits a 27in runner; a 36in+ staircase suits 30-32in; a narrow 30in staircase suits 24in.
- Standard widths: 24in, 27in, 30in, 32in and 36in (60-90cm).
- Aim for 3-4in (7-10cm) of bare stair showing on each side.
- Measure at the narrowest step — staircases are rarely perfectly parallel.
- Wider than 32in usually means a cut-and-bind order from broadloom carpet.
How to choose your stair runner width
Runner width is a proportion decision, not just a measurement. Measure wall-to-wall (or wall-to-balustrade) at the narrowest tread on the flight, then subtract the runner width and split the remainder between the two sides. That leftover strip of bare stair is the reveal, and it is what makes a runner look like a designed choice rather than a carpet that shrank.
| Stair width | Common runner width | Reveal each side |
|---|---|---|
| 30in / 76cm | 24in / 60cm | 3in / 7.5cm |
| 36in / 91cm | 27in / 70cm | 4.5in / 11cm |
| 36in / 91cm | 30in / 76cm | 3in / 7.5cm |
| 42in / 107cm | 32in / 80cm | 5in / 12.5cm |
| 48in / 122cm | 36in / 90cm | 6in / 15cm |
Check the balustrade, not just the wall
Where a staircase is open on one side, measure from the wall to the inside face of the spindles. The runner has to sit clear of the spindle bases or it will bunch as it turns onto each tread.
When to go narrower or wider
- Go narrower on a period staircase with attractive timber — a bigger reveal shows it off.
- Go wider on a busy family staircase where the runner is doing real protective work.
- Go narrower with a bold pattern, which reads as louder over a bigger area.
- Go custom if a standard width leaves you under 1.5in or over 6in of reveal.
Standard stair runner widths explained
Stock stair runner widths cluster around a handful of sizes because looms and binding lines are set up for them. 27in (about 70cm) is the default in most of the market, 24in and 30in cover narrower and wider staircases, and 32in or 36in are aimed at grand entrance flights. Anything outside that list is a cut-and-bind order from broadloom, which is easy to arrange but adds a per-metre binding charge and lead time.
- 24in / 60cm — cottage and secondary staircases, or where you want a wide timber reveal.
- 27in / 70cm — the default; suits the common 36in staircase with a balanced 4.5in reveal.
- 30in / 76cm — busier family stairs where you want more of the tread protected.
- 32in / 80cm — wide hallway staircases of about 42in.
- 36in / 90cm — grand entrance flights of 48in and over.
Width on winders, curved treads and open sides
Winder and curved treads are the reason the narrowest step rules the decision. On a turn, the inside of the tread pinches while the outside flares, and the runner has to stay clear of the newel and spindle bases through the whole sweep. If a standard width leaves less than about 1.5in of reveal at the tightest point, drop a size rather than fighting it on site — a runner that touches the spindles will ripple every time someone walks on it.
Keep the reveal even
Uneven reveal is the single most common thing that makes a professionally fitted runner look wrong. Snap a centre line up the flight before fixing anything, and measure the reveal on both sides at every third step as you go.
Know your numbers in 30 seconds
Enter your step count, tread depth and riser height — the stair runner calculator gives you the exact length to order, in metres and feet, with waste included.
Open the stair runner calculatorWhatever you decide, get the numbers first: the stair runner calculator doubles as a stair runner length calculator, adding nosing wrap, landings, winders, pattern repeat and waste so you order the right length the first time.
Still deciding on material, width or pattern? Our hub on stair runners compares weaves, widths, backings and fitting styles side by side, then hands the numbers straight to the calculator.
Frequently asked questions
What width should a stair runner be?
Most stair runners are 27in (70cm) wide, which suits the standard 36in staircase and leaves about 4.5in of bare wood each side. Widths of 24in, 30in and 32in are also common, and anything else is a custom cut-and-bind order.
How much stair should show either side of a runner?
Aim for 3–4in (7.5–10cm) of exposed stair on each side. Less than about 1.5in looks like a failed wall-to-wall carpet; much more than 5in makes the runner look undersized on the flight.
Should the runner be the same width all the way up?
Yes — measure the narrowest step and size the runner to that. Staircases are rarely perfectly parallel, and a runner that fits the widest step will crowd the narrowest one.
Can I get a custom width stair runner?
Yes. Most suppliers will cut broadloom to your width and bind or whip the edges, typically for a per-metre binding charge. It is the usual answer for very narrow or unusually wide staircases.
Do I need an account to use the stair runner width calculator?
Yes — the width calculator sits behind a free account so your stair measurements, preferred reveal and runner widths save against your projects. The stair runner length calculator on the home page is open to everyone with no sign-up.
How do I measure stair width for a runner?
Measure wall-to-wall (or wall to the inside face of the spindles) across each tread, at the back of the tread where the runner actually sits. Check at least three steps — top, middle and bottom — and size the runner to the narrowest reading.
Does runner width change how much runner I need?
It does not change the length you need, but it changes the cost. Runners are usually priced per linear metre or foot at a given width, so a 32in runner costs more per metre than a 27in one over exactly the same staircase length.