Interior Finishing Calculators
Paint, tile and flooring quantity calculators for rooms of any size. Every tool shows its formula and sources, and works in imperial or metric.
Calculators
Paint Calculator
Wall and ceiling area minus openings, coats and coverage: gallons and quarts or litres and tins.
Tile & Flooring Calculator
Tiles, boxes, waste for straight, offset, diagonal or herringbone layouts, plus grout.
Guides
Guide
How Much Paint for a 12×12 Room?
How many gallons of paint a 12×12 room needs for walls and ceiling with 8, 9 or 10 ft walls, one or two coats, plus the metric version in litres.
GuideHow to Calculate Square Footage for Odd-Shaped Rooms (and Square Metres)
How to measure square footage or square metres for L-shaped rooms, triangles, bay windows and curves, convert feet and inches, and avoid common mistakes.