Tiling a bathroom, kitchen, or backsplash? Just enter your room dimensions and tile size, and our free tile calculator tells you exactly how many tiles to buy â with the right waste factor built in. No guesswork, no running short, no wasted money on extra boxes. Perfect for DIYers and pros alike.
Modify the values and click the calculate button to use
Tile Size:
Area to Cover:
grout spacing, use negative for overlaps
Pretty much anyone doing a tiling project:
DIY homeowners
You're tiling your own bathroom or kitchen. You don't want to mess up the math.
Contractors
You need accurate estimates for bids and material orders.
Interior designers
You're planning a space and need to know costs.
Students
Maybe you're learning about construction math.
No matter who you are, the goal is the same: get the right number of tiles without wasting money.
Using the calculator is simple. Here's what you do:
Measure your space - Get the length and width of the area you're tiling. Use a tape measure. Measure twice.
Enter the dimensions - Put the length and width into the calculator. Make sure you're using the same unit (feet, inches, meters).
Enter tile size - Tell the calculator the size of your tiles. Common sizes are 12Ã12 inches, 6Ã6 inches, or 18Ã18 inches.
Add waste factor - This is the extra percentage you need for cuts and mistakes. We'll talk about this more in a minute.
Hit calculate - The calculator gives you the number of tiles you need.
Most rooms aren't perfect rectangles. For L-shaped rooms: split into two rectangles, measure separately, add together. For rooms with closets: measure main room and closet separately, add together. For rooms with angles: draw on graph paper, break into triangles and rectangles. Or just use the longest length and width â you'll have more waste but won't run out.
Here's something most people get wrong. You can't just buy exactly the number of tiles you need. You need extra.
Cuts - You'll have to cut tiles to fit edges. Some cuts will break.
Mistakes - You might mess up a cut. It happens.
Broken tiles - Some tiles might be damaged in shipping or during installation.
Future repairs - If a tile cracks later, you'll want a spare that matches.
How much extra?
Our calculator lets you set your own waste percentage. If you're not sure, start with 10% for a simple job.
The pattern you choose changes how many tiles you need. Here's why:
Straight Lay
10% waste
Simplest pattern. Tiles lined up in rows. Least waste.
Diagonal Pattern
15% waste
Tiles at 45-degree angle. Looks great but more cuts at edges.
Herringbone
20-25% waste
V-shaped pattern. Uses a lot more tile because of all the cuts.
Brick Pattern
10% waste
Tiles offset like bricks. Similar waste to straight lay.
Our calculator works for any pattern. Just adjust the waste factor based on what you're doing.
For walls:
Subtract windows and doors. Measure wall area, then subtract window and door areas. Don't forget trim around doors and windows.
For floors:
You usually don't have to subtract much. Maybe a toilet flange or floor vent. But those are small and won't change your count much.
For showers:
More complex. You have walls, a floor, and maybe a niche. Measure each surface separately. Shower walls often have different tile sizes than the floor.
Mistake #1: Not measuring correctly.
Measure twice. Use a tape measure, not a ruler. And make sure you're measuring in the same unit.
Mistake #2: Forgetting the waste factor.
This is the most common mistake. People buy exactly the number of tiles the calculator says, then run out.
Mistake #3: Not accounting for grout lines.
Grout lines take up space. If you're using wide grout lines, you might need slightly fewer tiles. But for most projects, the difference is tiny.
Mistake #4: Buying tiles from different batches.
Tile colors can vary between batches. Buy all your tiles at once. If you need more later, they might not match.
Mistake #5: Not keeping spare tiles.
Keep a few extra tiles after the job. If a tile cracks in a year, you'll be glad you have a match.
5 ft à 8 ft = 40 sq ft. Using 12Ã12 inch tiles (1 sq ft each). You need 40 tiles + 10% waste = 44 tiles total.
10 ft wide à 2 ft tall = 20 sq ft. Using 4Ã4 inch tiles (0.11 sq ft each) = about 182 tiles. Subtract a 3Ã2 ft window (6 sq ft). Now 14 sq ft = about 127 tiles + 10% waste = 140 tiles.
20 ft à 15 ft = 300 sq ft. Using 6Ã6 inch tiles (0.25 sq ft each) = 1,200 tiles. Herringbone needs 20% waste = 240 extra. Total: 1,440 tiles.
So you bought extra tiles and now you have leftovers. What do you do?
Keep them. Store a few tiles in your garage or basement. If a tile cracks later, you'll have a perfect match.
Return them. Most home improvement stores accept returns on unopened boxes. Check the return policy first â some have a 30-day window.
Donate them. Habitat for Humanity ReStore accepts tile donations. It's a tax write-off.
Use them for another project. Maybe a small backsplash or a craft project.
Use a tile layout calculator. Helps figure out where to start your pattern so you don't end up with tiny cuts at edges.
Account for tile thickness. Thick tiles (like natural stone) may need more space for cuts.
Consider the tile's shape. Rectangular tiles (subway tiles) need different calculations than square tiles. Our calculator handles both.
Don't forget the bullnose. Bullnose tiles are for edges and corners â calculate them separately from field tiles.
Did you know people have been using tiles for thousands of years? The oldest known tiles date back to ancient Egypt, around 4000 BC. They were made from mud and straw.
Romans used tiles for floors and roofs. They even had heated floors with tiles. Pretty fancy for 2000 years ago.
Today, tiles are made from ceramic, porcelain, glass, stone, and even recycled materials. The math for calculating how many you need hasn't changed much, though. It's still about area and waste.
You could do the math by hand. But why would you? Our calculator is:
Free
No sign-ups, no fees.
Accurate
Handles waste, patterns, and different units.
Easy
Just enter your numbers and go.
Fast
Get your answer in seconds.
Plus, you can use it on your phone or computer. So you can measure your room, then calculate right there. Go ahead â measure your space, pick your tiles, and use our calculator. You'll know exactly how many tiles to buy. No guesswork. No wasted money.
For a 12Ã12 room (144 square feet) with 12Ã12 inch tiles, you'd need 144 tiles for a perfect fit. But you should add 10% for waste, so buy about 158 tiles. This accounts for cuts and mistakes.
Measure the length and width of your bathroom floor. Multiply them to get the area. Then divide by the area of one tile. Add 10% for waste. Don't forget to subtract the area of the toilet flange if it's large.
For a simple straight lay, buy 10% extra. For diagonal patterns, buy 15% extra. For herringbone or complex patterns, buy 20% extra. If you're a beginner, add a bit more â you'll make more mistakes.
Measure the width and height of your backsplash area. Multiply to get the area. Subtract windows and outlets. Divide by the tile area. Add 10% for waste. Backsplash tiles are often smaller than floor tiles.
Break the room into smaller rectangles. Measure each one separately. Add the areas together. For L-shaped rooms, this works perfectly. For complex shapes, draw it out first.
Wider grout lines take up slightly more space, meaning you might need marginally fewer tiles. For most projects with standard grout lines (1/8" to 1/4"), the difference is negligible and the waste factor covers it.
Yes. Tile colors and shades can vary between production batches. Buying all tiles at once ensures they all match. If you need more later, the new batch might look noticeably different.
Keep at least 5-10 tiles from the original batch. Store them somewhere accessible. If a tile cracks or gets damaged years later, you'll have a perfect match that's impossible to find otherwise.
Yes, in some cases. The existing tile must be firmly attached with no cracks or loose pieces. You'll need a special bonding primer. But remember â tiling over tile raises the floor height, which can affect doors and transitions.
Porcelain is denser, more water-resistant, and more durable than ceramic. Porcelain is better for high-moisture areas like bathrooms and outdoor use. Ceramic is easier to cut and usually cheaper. Both calculate the same way.
Measure the shower floor dimensions. For square or rectangular showers, it's length à width. For custom shapes, break into smaller rectangles. Add 15% waste minimum â shower floors have a slope and drain cuts.
If you're doing a large area (over 100 sq ft), complex patterns like herringbone, natural stone tiles, or if the subfloor needs major prep work, hire a professional. Bad tiling is expensive to fix.
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