Tile Calculator: How Many Tiles Do I Need?

When calculating how many tiles you need for a project, consider the square footage of the area and your tile size. You can use our tile calculator below to calculate the number of individual tiles or boxes of tiles you need to purchase.

How Many Tiles Do I Need: Considerations

Tile Calculator: How Many Tiles Do I Need?

Estimate the number of tiles you need by determining the square footage of the area you’re tiling plus the square footage of each tile. For example, if you’re adding a tile floor to a 100-square-foot bathroom, and each tile is 12″ x 12″ (one square foot), you’ll need about 100 tiles. 

Enter the length and width of the room, as well as the width and length of the tile, waste factor, and gap size to calculate the number of tiles needed:



Doing rough calculations doesn’t account for spacer size or waste but can give you a general idea of how many tiles to purchase.

The formula for calculating floor tiles:

Square footage of floor ÷ square footage of one tile = the number of tiles you need

Here’s an in-depth look at what to consider when determining how many tiles you need.

The Square Footage of the Room

To determine the square footage of the area you’ll be tiling, measure the length and width in feet and multiply those numbers. For example, if your room is 12 feet long and 10 feet wide, multiply 10 x 12, which equals 120 square feet.

If the space you’re tiling is irregular, break it down into rectangular sections, find the square feet for each section by multiplying length x width in feet, and then add all totals together.

The Tile Size

You can purchase tile as small as ½ inch in diameter to 2+ feet long. The package your tile came in, or the online description, will indicate how many square feet each tile covers.

Spacer or Gap Size

When installing tile, you need to leave a small gap in between to fill with grout. The average spacer size for this ranges from 2mm to 5mm. 

If you’d like, you can account for spacer size when determining how many tiles you need. But spacer size won’t make a huge difference unless you’re tiling a large room.

Tile Orientation

The way you lay your tile has an impact on how much you need. For example, if you opt for a brick or herringbone layout, you’ll need about 10% more tile than a standard grid pattern.

Tile Waste Factor Percentage

Because tile breaks and intricate patterns may result in many unusable pieces, you need to add a 10% waste factor to the tile you purchase. For example, if your project calls for 120 square feet of tile, purchase 132 square feet to account for potential waste. If you’re laying a herringbone or angled pattern, add a 20% waste factor.

Whether you’re looking for a backsplash calculator or a granite-look tile estimator, our calculator above will let you account for tile size and spacing. You can add as much of a waste factor to the calculation as you’d like.

Frequently Asked Questions (FAQ)FAQ

What is the wall tiles calculation formula?

If you’re tiling your wall, measure the length and width of the area in inches and multiply those numbers to get square inches. Then, divide your square inches by 144 to determine the square footage. Next, look at your tile package to see how many square feet each tile covers. Divide your area square footage by the tile square footage – the answer is how many tiles you need.

How do you calculate adhesive tiles?

To calculate for adhesive tiles, find the square footage of the area you’re tiling. Then, look at your tile package to see how many square feet one tile covers. Divide your square footage to cover by the square footage of one tile.

How many square feet is one 2” x 2” tile?

A single 2 x 2-inch tile is 0.138889 square feet.