How to Measure for a Stair Runner: 2026 Pro Guide
By Keith Shannon — Master Carpet Installer (25+ years), Owner of DirectCarpet.com
Formula: (Number of stairs + ½) × 19 inches ÷ 12 = feet of runner needed.
Example: 12 stairs → 12.5 × 19 = 237.5 inches ÷ 12 = 19.8 ft → round up to 20 ft.
The 2 mistakes I see most
- Forgetting the top riser. People count their treads and measure one step, but they forget the last 6 to 7 inches going up to the hallway or main floor. Add about an inch more if you're putting underpad down. Our stair runner calculator adds the top riser in for you.
- Ordering the exact length. If you measure 18 feet and order 18 feet, you'll come up short. Like any carpet job, add 5 to 10% extra. Our how-to videos show you how to cut the last stair and fit the top riser so it finishes nice and clean.
Measuring your stairs for a runner doesn’t need to be confusing. Stair runners are sold by the foot and are absolutely a project a confident do-it-yourselfer can handle. I’ve installed thousands of runners across North America over the last 25+ years, and below I’ll show you the exact same way the pros measure — for length, for width, and for the tricky stuff like landings and curved stairs.
How Long Should My Stair Runner Be?
Every standard step uses about 19 inches of runner — that covers the tread (the part you step on) plus the riser (the vertical face). Multiply that by your number of stairs, remember to add the top riser, divide by 12, and round up.
The 3-step method
- Count your stairs. Don’t forget the top riser — count it as an extra half stair (so 12 stairs = 12.5 stairs of coverage).
- Multiply by 19 inches. (For chunky stairs with a big, deep nose, use 22 inches instead.)
- Divide by 12 to convert to feet, then round up to the next foot for safety.
Measuring step by step (with photos)
1. Measure one tread and riser together. Put your tape at the bottom of one riser, run it over the nose of the step and down to the bottom of the next riser. Most stairs come out around 18.5 to 19.5 inches.
2. Measure the top riser. Every staircase has one extra riser at the top going up to the hallway or landing. Put your tape under the nose of the top step down to the bottom of that riser. That usually adds 6 to 7 inches.
Stair Runner Length Cheat Sheet
Here's my cheat sheet. Each length covers this many stairs, counting the top riser as half a stair:
| Runner Length | Will Do |
|---|---|
| 18 ft | 11.5 stairs |
| 20 ft | 12.5 stairs |
| 22 ft | 13.5 stairs |
| 24 ft | 14.5 stairs |
| 26 ft | 15.5 stairs |
| 28 ft | 16.5 to 17.5 stairs |
Between two sizes? Always order the longer one. A few extra inches gets trimmed and hidden; a runner that’s too short can’t be fixed.
Use Our Pro Stair Runner Calculator →
How Wide Should My Stair Runner Be?
A stair runner should be about 6 to 8 inches narrower than your total stair width, which leaves a balanced 3 to 4 inches of wood showing on each side. But how much wood you show is partly a style choice, and it depends on the condition of your stairs:
- Covering up older, scratched or marked-up stairs? Show less wood. A 2 to 3 inch reveal on each side hides more of the imperfections.
- Beautiful new or freshly refinished hardwood? Show it off. A 4 to 6 inch reveal on each side lets that wood shine while still keeping the stairs safe underfoot.
- Older, slightly crooked stairs? A wider reveal actually helps — it disguises steps that aren’t perfectly straight (very common in older homes).
The most popular widths sold on DirectCarpet.com are 26 inches and 28 inches, with 28 inches being the runaway favorite. Machine-made runners commonly come in 27", 30", and 36" — and we also cut custom widths to whatever your staircase needs.
Measure stringer to stringer. Measure the full width of your stairs from side to side. For example, a 36-inch staircase with a 28-inch runner leaves 4 inches of wood showing on each side.
What You’ll Need to Measure
- A tape measure
- A calculator
- Paper to write down your numbers
Measure the tread depth and riser height on a couple of steps to confirm you’re in the normal 18.5"–19.5" range per step. If your steps are unusually deep or have a big bullnose, use 22 inches per step in the formula instead of 19.
Special Cases: Landings, Curves & Patterns
| Situation | What to do |
|---|---|
| Landings | Measure the landing separately and add that coverage to your total. |
| Curved / pie / winder stairs | Add extra length for the fanned steps, and template each turn. These are best left to a pro. |
| Patterned runners (herringbone, stripes) | Order extra so the installer can match the pattern across every step. |
Best Materials for a Stair Runner
- Nylon — the gold standard for durability and high-traffic homes.
- P.E.T. / Polyester — excellent stain resistance, a great pick for pet owners.
- Wool — premium, durable, and beautiful underfoot.
Read our full material guide: Polyester vs. Nylon →
DIY or Hire a Pro?
| Install type | Best for |
|---|---|
| DIY install | Standard straight staircases |
| Professional install | Curved, pie-shaped, or complex staircases with landings |
In North America we almost always install bottom-up: start at the first riser, staple under the nose, and use a knee-kicker to keep it tight as you work up the staircase. Watch my full DIY install tutorial →
Shop All Stair Runners → Open the Calculator →
Frequently Asked Questions
Can I order the exact length I measured?
No — always add 5 to 10% extra. If you measure 18 feet and order exactly 18 feet, you'll be short. The extra gets trimmed at the top riser, and our how-to videos show you how.
Do I need extra length if I'm using underpad?
Yes, add about an inch. The pad lifts the runner slightly, so it takes a little more carpet to wrap the stairs.
How do I measure my stairs for a runner?
Count your stairs, add half a stair for the top riser, multiply by 19 inches, and divide by 12 to get the length in feet. For example, 12 stairs = 12.5 × 19 ÷ 12 = 19.8 ft, which you round up to 20 ft.
How long should a stair runner be for 12 stairs?
For 12 standard stairs you need about 20 feet of runner. For stairs with a big, deep nose, use 22 inches per step (12.5 × 22 ÷ 12 ≈ 23 ft).
How wide should a stair runner be?
About 6 to 8 inches narrower than your stairs, leaving 3 to 4 inches of wood showing on each side. Show less wood (2–3 inches) to cover up worn stairs, or more (4–6 inches) to show off new hardwood. The most popular width sold is 28 inches.
Should I include the top riser when measuring?
Yes. Always add the top riser — count it as an extra half stair — or your runner will come up short at the top.
What if my staircase has a landing or a curve?
Measure landings separately and add that footage to your total. For curved, pie, or winder stairs, add extra length and template each turn — these are best handled by a professional installer.
Should I round up or down?
Always round up to the next foot. Excess is trimmed and tucked out of sight, but a runner cut too short can’t be salvaged.
Written by Keith Shannon, Master Stair Runner Installer with 25+ years of experience and owner of DirectCarpet.com. Every order helps support Save a Sato dog rescue in Puerto Rico.
Agree. Great info. Yet I need idea on how to measure a curved or wide to narrow staircase. I’m assuming I might have to order separate (and graduating m) sizes or separate pieces to accommodate different widths. Would love your help
Outstanding videos! You really do a great job explaining the process. How do I measure my two
Pie shaped steps for the runner?
Can you please provide instructions for measuring a winding/curve staircase for custom cutting? Thank you!
How do I measure only my treads I have 12 treads @ 36 1/8” wide X 12 1/2” deep and one landing 38” deep X 36 1/8” wide. I only want to carpet my treads only. My residents is non Loveland co and love your DIY!!!!! Pls let me know so I can order from you guys and I will be doing the installation myself. I have the tools already.
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