Room measurement calculators

Every material estimate starts with a measurement. These calculators turn length, width, and height into floor area, wall area, perimeter, and volume you can carry into any project.

Measurement calculators

Square Footage Calculator

Find floor area, square yards, and room perimeter from length and width.

Measurement

Room Size Calculator

Get floor, ceiling, and wall area plus room volume from one set of measurements.

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Wall Area Calculator

Calculate gross and net wall square footage after doors and windows.

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Measurement workflow

Work through it in order.

Each step feeds the next, so the measurement you trust becomes the quantity you buy.

  1. Step 01 Measure the floor Square Footage Calculator: Area and perimeter from length and width. Open calculator
  2. Step 02 Measure the walls Wall Area Calculator: Net wall area after doors and windows. Open calculator
  3. Step 03 See the whole room Room Size Calculator: Floor, ceiling, walls, and volume together. Open calculator

Measurement guides

Short, practical answers to go with the calculators.

All guides
Measurement guide

How to calculate square footage of a room

Measure rectangles, split L-shaped rooms, and convert between square feet, square yards, and square meters.

Common questions

Which measurement do I need for my project?

Floors (flooring, tile, carpet) need floor area. Paint, wallpaper, and drywall need wall area. Trim needs the perimeter. The room size calculator gives all of them at once.

Should I round my measurements?

Round each dimension up to the next inch. Material calculators then add an explicit allowance on top.

How do I measure an irregular room?

Split it into rectangles, measure each, and add the results. Calculate triangles as half of base × height.