Stair Runner Calculator

Step measurements
Standard residential stairs are 10″ tread, 7.5″ riser, 1″ nose overhang. Measure your actual stairs – older homes often have steeper, narrower stairs.

Number of steps
Count the steps you walk on, not the risers. A staircase between two floors typically has 13-15 treads. Do not include the landing or top floor.

Runner type
Waterfall is the easier DIY install – runner drapes over the nose with extra length built in. Hollywood is tighter and looks more tailored but takes more material.
For a typical 36″ wide staircase, leave 2-4 inches of stair tread visible on each side. A 32″ runner on a 36″ stair is the most popular look.

Runner needed
Length per step
0″
tread + riser + extra
Total runner length
0 ft
0 yds
Square footage
0
at chosen width
Padding (sq ft)
0
stair pad set or sheet
Includes 10% waste for cutting and pattern matching. Runners with bold patterns (stripes, large prints) need extra for matching at seams – add another 5-10%. Stair pads should match the tread width but be cut 2 inches shorter front and back so they do not show under the runner.
The Home Calc, calculators for your DIY projects

8 Tips for Measuring a Stair Runner: A Beginner’s Guide

Tip 1: Install Style Changes How Much Runner Each Step Actually Uses

Waterfall (flows over nose) lays the runner straight down each step and lets it fall naturally over the nose to the next tread, using less material per step, while Hollywood (wraps tight to riser) tucks the runner tightly into the crease where the tread meets the riser, which uses more material but creates a more tailored, formal look. Selecting the correct Install style keeps the calculator’s Length per step result accurate to the method you’re actually planning to use.

Tip 2: Tread Depth, Riser Height, and Nose Overhang All Feed Into One Number

The calculator combines your Tread depth (in), Riser height (in), and Nose overhang (in) to determine how much runner material each step consumes, since the runner has to travel across the flat tread, wrap or fall over the nose, and, in a Hollywood install, tuck down the riser. Measure each of these three dimensions on an actual step rather than assuming they’re uniform, especially in older homes.

Tip 3: Measure Several Steps, Not Just One, Before Trusting Your Numbers

Stairs in many homes, especially older ones, have slight variations in Tread depth (in) and Riser height (in) from step to step. Measure at least three or four steps and use the largest consistent figures for your Tread depth and Riser height entries, since underestimating either dimension leaves you short on material partway up the staircase.

Tip 4: Landings Need Their Own Measurement, Not an Estimate

If your staircase has a landing, select 1 landing or 2 landings and enter an accurate Landing depth (in), since a landing consumes runner material differently than a standard tread and is often deeper. Leaving Include landing(s)? set to No landing when your staircase actually has one will significantly undercount your Total runner length.

Tip 5: Runner Width Should Match What You’ve Already Chosen, Not the Widest Option

Select the Runner width, 27 inches, 32 inches, or 36 inches, that matches the actual runner product you’re planning to buy, since this determines your Square footage and Padding (sq ft) results, not just how it looks on the stairs. A wider runner covers more of the tread’s width but also costs more per linear foot, so confirm your choice before running the calculator.

Tip 6: Padding Isn’t Optional, It Extends the Runner’s Life

The calculator’s Padding (sq ft) result reflects that a stair runner needs its own padding underneath, distinct from any padding under adjoining carpet, since stairs see concentrated foot traffic and impact at the nose of each step. Skipping padding to save money leads to a runner that wears out and flattens far faster, especially at the leading edge of frequently used stairs.

Tip 7: Total Runner Length Should Include a Buffer for Pattern Matching and Waste

If your runner has a directional pattern or a repeat, like a stripe or a border design, add extra length on top of the calculator’s raw Total runner length result to account for aligning the pattern at each step and trimming the top and bottom ends cleanly. A plain or textured runner needs less buffer than a patterned one.

Tip 8: Number of Treads Should Count Every Step, Including Ones Near Landings

Count Number of treads (steps) carefully on a staircase with a landing or a turn, since it’s easy to miscount steps directly before or after a landing. An inaccurate step count throws off your Total runner length and Square footage results even if every individual measurement is otherwise correct.

Where to Go From Here

Now that you understand how install style, tread and riser measurements, landings, and runner width each affect how much material you’ll need, use our Stair Runner Calculator above to get your total runner length and padding. You’ll know exactly what to measure and double-check because you understand what’s driving the number.

Frequently Asked Questions About Stair Runners

What’s the difference between a Waterfall and a Hollywood install?

A Waterfall (flows over nose) install lays the runner flat down each tread and lets it fall naturally over the nose of the step without tucking into the crease, which is simpler to install and uses somewhat less material. A Hollywood (wraps tight to riser) install tucks the runner tightly into the crease between the tread and riser for a more tailored, formal look, but it uses more material per step and takes more precise installation work.

How do I measure tread depth and riser height accurately?

Measure Tread depth (in) as the horizontal distance from the front edge (nose) of the step to where it meets the riser above the next step down, and measure Riser height (in) as the vertical distance from one tread’s surface to the next. Measure a few different steps, since older homes often have slight variation between them, and use the largest consistent figures to avoid running short.

Do I really need padding under a stair runner?

Yes, padding significantly extends a stair runner’s life, since stairs experience concentrated foot impact right at the nose of each step, which wears down an unpadded runner much faster than padded flat flooring would. The calculator’s Padding (sq ft) result accounts for this, and it’s a worthwhile addition even if it wasn’t part of your original budget.

How do landings affect my total runner length?

A landing consumes runner material differently than a standard tread, since it’s typically a larger flat area rather than a single step, so selecting 1 landing or 2 landings and entering an accurate Landing depth (in) is necessary for an accurate Total runner length. Leaving this set to No landing when your staircase has one will significantly undercount how much runner you need to buy.

Should I buy extra runner beyond the calculator’s result?

Yes, especially if your runner has a directional pattern, stripe, or border design that needs to align consistently from step to step, since pattern matching uses more material than a plain or textured runner. Even for a plain runner, a small buffer covers trimming the top and bottom ends cleanly and protects against a measurement error on an unusually shaped staircase.