How Much Tile for a Kitchen Backsplash?

Updated 2026-07-19

A backsplash is the smallest tiling job in the house and the one everybody notices, because it sits at eye level between the countertop and the upper cabinets. The good news: the average kitchen only has about 30 square feet of backsplash, so the material bill stays modest. The bad news: it is exactly the kind of job where a homeowner buys the exact footage, makes two bad cuts on a mosaic sheet, and ends up one sheet short.

Measuring takes ten minutes with a tape and a notepad. The only wrinkle is that a backsplash is almost never one clean rectangle — it is a series of runs broken up by windows, outlets, and the range hood. Measure wall by wall and the math stays easy.

Step 1: Measure each run, wall by wall

Standard backsplash height is 18 inches — the gap between the countertop and the bottom of the upper cabinets. Convert that to 1.5 feet, then multiply by the length of each counter run. Write every wall down on its own line instead of totaling in your head.

1. Wall A: 10 ft of counter × 1.5 ft = 15 sq ft.
2. Wall B (the return wall): 8 ft × 1.5 ft = 12 sq ft.
3. Behind the range, most people tile up to the hood. Add the extra height: a 30-inch range opening going 2 more feet up is 2.5 × 2 = 5 sq ft.
4. Where there are no uppers — beside a window or on an open wall — decide your stopping height first and measure to that line.

Step 2: Subtract windows, ignore outlets

Subtract large openings only. A 3 × 2 foot window over the sink removes 6 real square feet of tile, so take it out of the total. Outlets and switch plates are the opposite: leave them in the number. Each one costs you a cut tile, and the square inches you would save by subtracting them never survive the wet saw.

Measure in inches, then convert. Walls wander. An 18-inch nominal gap might read 17.25 at one end and 18.5 at the other, and ordering to the optimistic number is how you come up short on the last row.

Worked example: the 30 sq ft kitchen

Add the runs: 15 + 12 + 5 = 32 sq ft. Subtract the window: 32 − 6 = 26 sq ft. That is your net coverage, and it lands right at the national average for a modest L-shaped kitchen.

Now apply waste. Ten percent for a straight subway layout takes you to 28.6 sq ft — call it 29. Planning a herringbone or diagonal set? Use 15%, which puts you at 30 sq ft even. Mosaic sheets are usually about 1 sq ft each, so the shopping list writes itself: 29 sheets, or 30 for the fancy pattern.

Translating square feet into boxes and sheets

Check coverage on the label before you fall in love with a tile. Classic 3 × 6 subway tile works out to exactly 8 pieces per square foot (each tile covers 18 square inches), so 29 sq ft means 232 pieces — three boxes if yours are packed 100 to a box. Sheet-mounted mosaics vary from 0.9 to 1.05 sq ft per sheet, so count sheets, not the marketing photo.

Buy everything from the same shelf lot, and grab one extra sheet or a handful of loose subway tiles for the garage shelf. Backsplashes get cracked by flying pot lids and over-enthusiastic stand mixers more often than you would think.

Backsplash mistakes to skip

When your wall-by-wall numbers are written down, run them through the tile calculator to sanity-check sheets, boxes, and waste before you head to the store.

1. Ordering exact net footage with zero waste — the number-one way to stall a one-weekend job.
2. Forgetting the return on the side of a cabinet run or the 2-inch strip behind the faucet.
3. Using a 10% waste factor on herringbone or intricate mosaics; use 15% and keep the leftovers.
4. Subtracting outlet openings. The cut tile is the outlet opening.
5. Assuming all mosaic sheets are exactly 1 sq ft. Check the label first.