Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Tiles needed
68
Boxes to buy
9
Area (sq ft)
120.0
Grout needed (lb)
6.6
Psst — share this and help Rex grow
One click, a permanent link with your numbers baked in.
How to use this
- 1Enter area width (ft).
- 2Enter area length (ft).
- 3Enter tile width (in).
- 4Enter tile length (in).
- 5Enter waste allowance (%).
- 6Enter tiles per box.
- 7Enter grout joint width (in).
- 8Read your tiles needed on the right — it updates as you type.
- 9Hit Share to keep the scenario or send it to someone.
About this calculator
Enter room dimensions and tile size to get tile count with waste allowance, boxes to buy, and the grout volume the joints will consume.
Worked example
Using the values the calculator loads with:
Inputs
- Area width: 10 ft
- Area length: 12 ft
- Tile width: 12 in
- Tile length: 24 in
- Waste allowance: 12 %
- Tiles per box: 8
- Grout joint width: 0.125 in
Results
- Tiles needed: 68
- Boxes to buy: 9
- Area (sq ft): 120
- Grout needed (lb): 6.6
What each field means
Inputs
- Area width (ft)
- The area width used in the calculation, measured in ft. Starts at 10 ft so you have a working example on load.
- Area length (ft)
- The area length used in the calculation, measured in ft. Starts at 12 ft so you have a working example on load.
- Tile width (in)
- The tile width used in the calculation, measured in in. Starts at 12 in so you have a working example on load.
- Tile length (in)
- The tile length used in the calculation, measured in in. Starts at 24 in so you have a working example on load.
- Waste allowance (%)
- The waste allowance used in the calculation, measured in %. Starts at 12 % so you have a working example on load. Accepted range: 0–40 %.
- Tiles per box
- The tiles per box used in the calculation. Starts at 8 so you have a working example on load.
- Grout joint width (in)
- The grout joint width used in the calculation, measured in in. Starts at 0.125 in so you have a working example on load.
Results
- Tiles needed
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Boxes to buy
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Area (sq ft)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Grout needed (lb)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How much waste should I plan?
10% for a simple square room, 15% for diagonal layouts, and 20% for lots of cuts around fixtures.
Should I buy extra for repairs?
Yes — one spare box. Dye lots change and a discontinued tile makes any future repair obvious.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Tile & Grout Quantity Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/wallpaper-tile-grout
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/wallpaper-tile-grout" target="_blank" rel="noopener">Tile & Grout Quantity Calculator — RevenueLab</a> (2026).</p>
Source: [Tile & Grout Quantity Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/wallpaper-tile-grout) (2026).