12x12 Tile Calculator
Ver en españolLast updated
Your room (12x12 tile)
Picking a pattern sets the recommended waste factor.
Check the box label — it varies by brand.
Tiles to buy
132 tiles
- Area to cover
- 120 sq ft
- Area including waste
- 132 sq ft
- Tile size
- 12 x 12 in
- One tile covers
- 1 sq ft
- Boxes needed
- 9 boxes
- Waste applied
- 10%
Tile is sold by the box — round up and keep one spare box from the same dye lot.
Save this calculation in the free app
Smart Tile Calculator keeps your tile jobs on your phone, offline. On iPhone? It's inside Roofing Calculator & Estimator.
🛒 Your tile setting materials list
#ad · Amazon- Polymer-modified thinset mortar2 × 40 lb bags for 120 sq ft
- Sanded grout in your colour8.5 lb for 1/8 in joints: pick the colour on Amazon (not added to the cart)
- 1/4 × 3/8 in square-notch trowel1 trowel
- Tile spacers, 1/8 in crosses1 bag of 1,000 (132 needed)
- Cement board screws, 1-1/4 to 1-5/8 in1 box of 600 (405 needed)
- Penetrating grout sealer1 × 16 oz bottle
Buy locally (tile shop or home center, so you can see the dye lot; boards ship as freight): Tile: 132 tiles (9 boxes) · Cement backer board: 9 × 3 × 5 ft sheets
Adds 5 items with these quantities to your Amazon cart; you review them there before buying. As an Amazon Associate I earn from qualifying purchases.
12x12 tile coverage chart
| Room area | Tiles (no waste) | Tiles +10% | Boxes (15/box) |
|---|---|---|---|
| 50 sq ft | 50 | 55 | 4 |
| 100 sq ft | 100 | 110 | 8 |
| 150 sq ft | 150 | 165 | 11 |
| 200 sq ft | 200 | 220 | 15 |
| 300 sq ft | 300 | 330 | 22 |
| 500 sq ft | 500 | 550 | 37 |
| 1,000 sq ft | 1,000 | 1,100 | 74 |
Box counts assume 15 tiles per box — confirm on the label before you order.
How many 12x12 tiles for common room sizes
Count is length × width in feet, because each 12x12 tile is one square foot. Add 10% for a straight lay and 15% for a diagonal lay, then divide by the tiles in your box and round up.
| Room | Sq ft | Tiles +10% (straight) | Tiles +15% (diagonal) | Boxes (15/box, straight) |
|---|---|---|---|---|
| 5 × 8 ft bathroom | 40 | 44 | 46 | 3 |
| 8 × 10 ft | 80 | 88 | 92 | 6 |
| 10 × 10 ft | 100 | 110 | 115 | 8 |
| 10 × 12 ft | 120 | 132 | 138 | 9 |
| 12 × 12 ft | 144 | 159 | 166 | 11 |
| 12 × 15 ft | 180 | 198 | 207 | 14 |
| 15 × 20 ft | 300 | 330 | 345 | 22 |
Rounded up to whole tiles and boxes. Measure an L-shaped room as two rectangles and add them.
Setting 12x12 tile: trowel, spacing and grout
A 1/4 × 3/8 × 1/4 in square-notch trowel is the usual choice for 12x12 tile, the notch Custom Building Products lists for tile from 8 to 16 in — check thetrowel size calculatorfor other sizes. Pull up a tile now and then to make sure the back is covered. Use 1/8 in spacers for standard 12x12 ceramic or porcelain, 3/16 in if the tile is not rectified and varies from box to box, and as little as 1/16 in for rectified porcelain on a flat floor (see the spacer guide). Work out bags of thinset and grout for the same room with thethinset calculatorand thegrout calculator.
Worked example: centre a tile or centre a joint?
Most 12x12 tile actually measures 11 7/8 in, so with a 1/8 in joint the pattern repeats every 12 in exactly. Take a room 127 in (10 ft 7 in) wide:
| Start | Cut at the walls |
|---|---|
| Full tile against one wall | 7 in on the far wall only |
| Joint on the centre line | 3.4 in on both walls (thin strips) |
| Tile centred on the centre line | 9.4 in on both walls (balanced) |
Here centring a tile wins: both walls get cuts of about 9.4 in, which look deliberate. Centring a joint leaves 3.4 in strips that snap badly and draw the eye. In a different width the answer flips, so work out both before you snap the first chalk line. Do the same across the other direction of the room. Then check the room is square with a 3-4-5 triangle (3 ft along one wall, 4 ft along the other, 5 ft across) so the rows do not drift against the far wall.
Thinset, grout and box weight for 12x12
| Room area | Thinset, 50 lb bags | Sanded grout | 25 lb grout bags | Tile weight (porcelain) |
|---|---|---|---|---|
| 50 sq ft | 1 | 3.5 lb | 1 | 248 lb |
| 100 sq ft | 2 | 7.1 lb | 1 | 495 lb |
| 150 sq ft | 2 | 10.6 lb | 1 | 743 lb |
| 200 sq ft | 3 | 14.1 lb | 1 | 990 lb |
| 300 sq ft | 4 | 21.2 lb | 1 | 1,485 lb |
Thinset at about 75 sq ft per 50 lb bag with a 1/4 x 3/8 in square notch. Grout for 3/8 in thick tile with 1/8 in joints, plus 10% in the bag count. Tile weight at 4.5 lb per sq ft including 10% waste; ceramic is about a fifth lighter.
One 12x12 porcelain tile weighs about 4.5 lb, so a box of 15 is about 68 lb. Ceramic 12x12 is closer to 3.5 lb a tile. The tile weight calculator adds up the whole floor build.
How high the finished floor will be
A tile floor raises the floor more than people expect, and the doorway is where it shows. Over a wood subfloor, 3/8 in tile + about 1/8 in of thinset + 1/4 in cement board + another 1/8 in thinset bed under the board comes to about 7/8 in. An uncoupling membrane (about 1/8 in thick) in place of the board brings it to about 3/4 in. Measure the floor next door before you start: if the difference is over 1/4 in you need a reducer or transition strip, and the door may need trimming. Check that the toilet flange will sit on top of the finished tile, not below it.
Common 12x12 mistakes
- Ordering exactly the square footage. 12x12 makes the math feel exact, but cuts at every wall, the toilet and the door casing all come out of waste. Order 10% over for a straight lay, 15% for diagonal, and keep a spare box. A later batch may not match.
- Starting from the most visible wall without checking the far one. Walls are rarely straight or parallel. A dry row in both directions shows where the thin cuts land before any mortar is mixed.
- Using a 1/16 in joint on pressed ceramic. Pressed 12x12 often varies by 1/32 in or more, which needs at least a 3/32 in joint. Use 1/8 in, or 3/16 in if the tiles vary more.
- Treating mosaic sheets as tiles. “12x12” mosaic sheets are often 11 3/4 in or 12 in square including the joints. Count sheets, check the actual sheet size on the box, and space sheet to sheet at the same joint as inside the sheet.
How we worked these numbers
- Tile and box counts: area x (1 + waste), divided by 1 sq ft per tile, rounded up to whole tiles and then whole boxes (15 per box unless you change it).
- Layout cuts divide each half of the room by the 12 in repeat (11 7/8 in tile + 1/8 in joint) and report what is left at the wall.
- Grout uses the joint-volume formula from the grout calculator for 3/8 in tile at a full-depth 1/8 in joint, sanded grout at 110 lb/cu ft.
- Thinset uses about 75 sq ft per 50 lb bag with a 1/4 x 3/8 in square notch. Build-up heights are typical thicknesses of each layer, not one product's spec.
Written and checked by the Smart Tile Calculator team. Every table on this page is computed by the same code as the calculator, so the two cannot disagree. Last checked .
Popular 12x12 floor tile and setting supplies
Smart Squares Easy Street Plush Carpet Tiles (Sample, 487 Porcelain) | Made in the USA, Premium 18x18 Peel and Stick Floor Tiles with Attached Padding – Seamless DIY Carpet Squares
$8.97
Check price on Amazon
Tile Leveling Compounds System Plier Hand Floor Pliers Tiling Installation Locator Leveling System for DIY Ceramic Stone Wall Tile Spacers Adjustment yellow
$13.99
Check price on Amazon
Drydiet 108 Sqft Uncoupling Membrane for Tile 1/8''(3mm), Orange | 3.28 x 32.8 FT Waterproofing Uncoupling Membrane Roll, Anti-Fracture Flooring Underlayment for Shower Bathroom Kitchen
$134.99
Check price on Amazon
Nuanchu Tile Leveling System Kit 200 Reusable Tile Spacers + 200 1/16'' Replaceable Spare Steel T-pin, Leveling Clips Fit 8-12mm Floor Compounds Set for Wall & Floor (Yellow)
$32.99
Check price on Amazon
As an Amazon Associate I earn from qualifying purchases.
Prices as of Oct 17, 2026, 4:39 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.
Tools the pros use for this job
12x12 Porcelain Tile
Smart Squares Easy Street Plush Carpet Tiles (Sample, 487 Porcelain) | Made in the USA, Premium 18x18 Peel and Stick Floor Tiles with Attached Padding – Seamless DIY Carpet Squares
$8.97
Check price on AmazonPorcelain in 12x12 is the workhorse floor tile — hard, cheap per sq ft, easy to cut.
Snap Tile Cutter
VEVOR Manual Tile Cutter, 24 inch, Porcelain Ceramic Tile Cutter with Tungsten Carbide Cutting Wheel, Infrared Positioning, Anti-Skid Feet, Durable Rails for professional installers or beginners
$80.90
Check price on Amazon12x12 ceramic scores and snaps cleanly — no wet saw needed for straight cuts.
1/8 in Tile Spacers
DGSL Tile Leveling System Tile Spacers 1/8 Inch, 300 pieces Horseshoe Shim U Shape Plastic Tile Leveling Clips for Various Types of Tile Leveling
$15.03
Check price on AmazonThe standard joint for 12x12 tile — consistent lines make the floor look square.
As an Amazon Associate I earn from qualifying purchases.
Prices as of Oct 17, 2026, 4:39 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.
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
Because one 12x12 tile equals one square foot, tiles needed ≈ square feet needed. A 10 ft × 12 ft room is 120 sq ft, so 120 tiles before waste and 132 tiles at 10% waste. The only trap is box math: 12x12 tile ships in boxes of 12–17 tiles depending on brand, so 132 tiles at 15 per box is 9 boxes, not 8.8.
Steps: measure the room at its widest points, subtract nothing smaller than a closet, add 10% waste (15% for a diagonal layout), divide by tiles per box, then round up and add one spare box for future repairs.
For nominal-vs-actual sizing: most 12x12 tiles measure 11 7/8" so the grout joint makes up the difference. Do not try to lay them out at exactly 12" on center without checking a dry row first — see the spacer size guide. Different size? 12x24 and every other size have their own calculators, and the tiles per square foot chart covers box conversions.
Frequently asked questions
How many 12x12 tiles do I need for 100 square feet?
100 tiles exactly, before waste. With a 10% waste factor buy 110 tiles — about 8 boxes if your box holds 15 tiles.
How many 12x12 tiles are in a box?
Most brands pack 12 to 17 tiles per box, covering 12–17 square feet. Home Depot and Lowe's house brands are usually 15 or 16 per box.
How many 12x12 tiles per square foot?
One. A 12x12 tile is exactly one square foot of coverage, ignoring grout joints.
How many 12x12 tiles do I need for a 10x10 room?
A 10x10 room is 100 sq ft, so 100 tiles before waste, 110 with 10% waste for a straight lay (8 boxes of 15) and 115 for a diagonal lay.
How many 12x12 tiles for a 10x12 room?
120 tiles before waste. Buy 132 for a straight lay — 9 boxes of 15 — or 138 for a diagonal lay.
What size trowel do I use for 12x12 tile?
A 1/4 × 3/8 × 1/4 in square-notch trowel, the size Custom Building Products lists for tile from 8 to 16 in. Go up a size if a lifted tile shows bare spots on its back.
Are 12x12 tiles out of style?
For floors, larger formats like 12x24 dominate new builds, but 12x12 is still the cheapest per square foot and the easiest DIY size to cut and set.
Related calculators
- 12x24 Tile CalculatorThe most popular plank size — counts, boxes and offset rules.
- 24x24 & All-Size CalculatorEvery common tile size from 2x2 mosaic to 24x48 slab in one dropdown, with notes for each size.
- Tiles Per Square Foot ChartReverse calculator and master chart: tiles per sq ft and per box.
- Tile Waste Factor GuideHow much extra tile to order, by pattern and room complexity.
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.