Free home project calculator
Tile Calculator
Convert room area and tile size into a whole-tile estimate with a chosen waste allowance.
What this calculator does
The tool converts one tile to the selected area unit, divides total area by tile area, applies waste, rounds up to whole tiles and then rounds up to whole boxes.
Before entering numbers
Sketch the project and label every dimension with its unit. Break irregular areas into rectangles, measure each separately, and note areas that are excluded. Use finished dimensions where compaction, joints or built-up layers matter.
How to get a more reliable estimate
Measure twice from fixed reference points. When opposite sides differ, do not average blindly: the shape may be out of square and the layout may create additional cuts. For packaged materials, copy coverage and yield directly from the current product data rather than an old listing or generic rule.
Allowance is not the same as profit margin or contingency. It covers realistic cutting, breakage, spillage or pattern loss. The right percentage changes with material size, room complexity, installer experience and whether matching replacement material will be available later.
Use these checks
- Measure niches, returns and skirting separately.
- Diagonal, patterned and small-room layouts need more allowance.
- Buy one shade/calibre batch where the manufacturer uses batch codes.
- Keep spare tiles for future repairs.
Save the inputs with the supplier quote. If the purchased quantity differs sharply from this result, ask what assumption changed: measured area, unit conversion, product coverage, layer thickness, waste or package rounding.
Related planning guides
Calculation transparency
ZHowTo calculators run in your browser and use the values shown in the form. No result is sent to a server. The method is explained above so you can reproduce the arithmetic independently or challenge an assumption.