Stair Tile Calculator
Your stairs
3/8 in porcelain on a typical thin-set bed is about 1/2 in.
Tiles to buy
55 tiles
- Per tread / per riser
- 2 / 2
- Area
- 55.1 sq ft (treads 31.5, risers 23.6)
- Front edge
- 36 pieces (36 ft)
- Bottom / top riser after tile
- 7.75 in / 7.25 in
- IRC riser & tread check
- Check: risers vary by 0.5 in (limit 0.375 in)
Tiles are counted per step without reusing offcuts, plus your waste allowance.
Tools the pros use for this job
Stair Nosing Trim
White Caulk Tape Waterproof Self Adhesive, Toilet & Bathtub Sealant Strip, Peel & Stick Caulking Tape for Floor Tile Corner Trim & Shower, Bathroom Accessories, Better Than Silicone Caulk
$9.98
Check price on AmazonProtects the front edge where a tread tile would chip.
Wet Tile Saw
Every tread and riser needs a clean rip cut.
Tile Leveling Clips
DGSL Tile Leveling System with Plier, 300 Tile Spacers 1/8" and 100 Wedges
$25.99
Check price on AmazonKeeps long plank tiles flush on narrow treads.
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Prices as of Oct 2, 2026, 4:36 AM UTC. Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply to the purchase of this product.
Tiles for common staircases
| Flight (36 in wide) | 12 × 24 tile | 6 × 36 plank | Area |
|---|---|---|---|
| 3 treads, 4 risers | 16 tiles | 16 planks | 15.1 sq ft |
| 7 treads, 8 risers | 33 tiles | 33 planks | 32.9 sq ft |
| 12 treads, 13 risers | 55 tiles | 55 planks | 55.1 sq ft |
| 14 treads, 15 risers | 64 tiles | 64 planks | 63.9 sq ft |
10.5 in treads, 7.25 in risers, 1/8 in joints, 10% waste. A 6 × 36 plank needs two rows on a 10.5 in tread, one of them ripped to about 4.4 in.
How to tile stairs
Check the stairs are solid first: a tread that flexes will crack tile. Over wood stairs, screw down loose treads and add an uncoupling membrane or a backer suited to the floor; concrete stairs take tile directly once clean and sound. Tile the risers first, working from the top down, so the tread tile sits on top of the riser tile and hides its top edge. Then set the treads with the finished nosing at the front, a full tile there and any cut piece at the back against the riser. Back-butter every piece — a stair edge takes heavy point loads.
Porcelain with a textured or matte finish is the usual choice for stairs because a polished tile is slippery on a step. See the tile edge trim calculator for metal nosing and the bullnose tile calculator for tile edge pieces.
Do this math on the job site — in the free app
Smart Tile Calculator for Android: offline, in your pocket, free.
How this calculator works
Tiles per step. The tile runs with its long side across the stair. Tiles across = ceil((stair width + joint) ÷ (tile length + joint)); rows front to back = ceil((tread depth + joint) ÷ (tile width + joint)). Risers use the riser height in place of the tread depth. Multiply by the number of treads and risers, then add waste. A straight flight has one more riser than treads.
Nosing. The front edge of each tread is finished with stair-nose or bullnose tile, or a metal nosing profile: one stair width per tread.
Riser check. Tile plus thin-set raises every tread by the same amount, so the middle risers keep their height. The bottom riser grows by the build-up unless the floor below is tiled too, and the top riser shrinks by it unless the landing is tiled. The 2021 IRC (R311.7.5.1) allows a 7.75 in maximum riser and only 0.375 in between the tallest and shortest riser in a flight; treads must be at least 10 in deep (R311.7.5.2).
Worked example. 12 treads and 13 risers, 36 in wide, 10.5 in treads, 7.25 in risers, 12 × 24 tile with 1/8 in joints: 2 tiles across, 1 row per tread and 1 per riser, so 24 + 26 = 50 tiles, 55 with 10% waste, covering 55.1 sq ft. With a 1/2 in build-up and an untiled floor at the bottom, the bottom riser becomes 7.75 in — right at the limit — and the flight varies by 1/2 in, more than the 3/8 in allowed.
Frequently asked questions
How many tiles do I need for stairs?
Count step by step: tiles across the width × rows on each tread, plus the same for each riser, then add 10%. A 12-tread, 13-riser flight 36 in wide with 12 × 24 tile needs 2 tiles per tread and 2 per riser — 50 tiles, 55 with waste.
How many square feet is a staircase?
Treads are width × depth and risers width × height. A 36 in wide flight with 10.5 in treads and 7.25 in risers is about 2.6 sq ft per tread and 1.8 per riser: 55.1 sq ft for 12 treads and 13 risers.
Does tiling stairs change the riser height?
Yes, at the top and bottom. Tile and thin-set raise every tread by the same amount, so the bottom riser gets taller and the top one shorter unless the floor and landing are tiled too. The IRC allows only 3/8 in between the tallest and shortest riser in a flight.
What is the best tile for stairs?
A porcelain tile with a matte or textured, slip-resistant finish, with a stair-nose piece or a metal nosing on the front edge. Avoid polished tile on treads.
Should you tile the riser or the tread first?
The riser first, so the tread tile overlaps the top of the riser tile and hides its cut edge.
Related calculators
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- Floor Tile CalculatorTiles and boxes for any floor, by room dimensions and tile size.
- Tile Edge Trim CalculatorSticks of Schluter or 8 ft edge trim for every exposed edge, plus profile height.
- Bullnose Tile CalculatorBullnose pieces for backsplash, shower and wainscot edges, plus corner pieces.
Guides worth reading next
- How to Measure a Room for Tile (Step by Step)Measure any room for floor or wall tile: handle closets and alcoves, convert inches to decimals, subtract fixtures, and add the right waste percentage.
- Choosing the Right Tile Size for Your RoomHow tile size changes a room: when 12×24 beats 4×4, why small rooms can take large tile, grout line math, and the flatness rule for big formats.
- Sanded vs Unsanded vs Epoxy Grout: Which One Do You Need?Grout types explained by joint width and location: when sand scratches tile, why epoxy wins in showers, and how much of each type a bag actually covers.