How this calculator works
A backsplash is a rectangle, so the area is the length times the height, less any opening. The tile count divides that area by the area of one tile plus its joint, adds the waste and rounds up. Grout is worked from the joint volume as in the tile calculator.
Worked example: 10 ft of counter with an 18 in backsplash is 15.0 ft². In 3 × 6 in subway tile with 1/8 in joints and 10% extra that is 125 tiles (13 boxes of 10) and 2.3 lb of grout. A 6 ft² window opening takes it to 75 tiles. In 12 in mosaic sheets, an 8 ft run needs 14 sheets.
Assumptions and sources
- Assumptions used: 10% waste added; 6 × 3 in tiles with 0.125 in joints, 0.25 in thick; grout at 20% extra (about 100 lb of grout per cubic foot of joint).
- Grout is the same joint-volume method as the tile calculator. Where the backsplash meets the counter, the walls and the cabinets, a flexible caulk in the grout color is used instead of grout, because the joints move. Ask whether the stove area needs a heat-rated adhesive: use the maker's instructions.
The formula and a worked example are shown above, so you can check any result by hand. Read how we calculate and check our numbers. Results are estimates for planning: supplier products vary, so check the size printed on the label.
Tiles for a backsplash by length
18 in high, 3 × 6 in subway tile with 1/8 in joints, 10% extra, no openings.
| Length of counter | Area | Tiles | Grout |
|---|---|---|---|
| 6 ft | 9.0 ft² | 75 | 1.4 lb |
| 8 ft | 12.0 ft² | 100 | 1.9 lb |
| 10 ft | 15.0 ft² | 125 | 2.3 lb |
| 12 ft | 18.0 ft² | 149 | 2.8 lb |
| 15 ft | 22.5 ft² | 187 | 3.5 lb |
| 20 ft | 30.0 ft² | 249 | 4.7 lb |
Tips before you buy
- Measure the height from the counter to the underside of the wall cabinets, and check the wall with a level: counters and cabinets are often not level, which shows at the top row.
- Tile behind the range up to the hood or the cabinets if you can. A grease splash goes higher than you expect.
- Switch off the power at the breaker before you work at outlets, and use box extenders so the outlet sits flush with the new surface.
- Use caulk, not grout, at the counter and at the inside corners. Grout cracks where two surfaces move.
- Buy one extra box from the same lot. A single chipped tile near the stove is hard to match later.
Tools & materials for this project
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Frequently asked questions
How many tiles do I need for a kitchen backsplash?
Multiply the length of the counter by the height of the backsplash, take off openings, and divide by the area of one tile with its joint. A — ft run, 18 in high, in 3 × 6 in subway tile needs 125 tiles with 10% extra.
How high should a backsplash be?
A short one is about 4 in, which protects the wall behind the counter. A full-height one runs up to the underside of the wall cabinets, which is often 18 in above the counter. Behind a range or sink it may go higher.
How much grout does a backsplash need?
Small tiles and wide joints take more. The default backsplash takes 2.3 lb in 1/8 in joints, which is one small bag or tub.
Do I tile around outlets?
Yes, and you cut the tile to fit. Switch off the power first and use box extenders so the outlet is flush with the new surface.
Grout or caulk at the counter?
Use caulk. The counter and the wall move at different rates, and rigid grout cracks at the joint.
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Related calculators & guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.