CalcReed

Home & DIY calculator

Square Footage Calculator

Enter two dimensions and get the usable area before you order material.

Your measurements

Metric + imperial

How this calculator works

Area = length × width. Purchase area = area × (1 + waste percentage ÷ 100).

Worked example

A 12 ft × 10 ft room has 120 ft². With 10% waste, plan for 132 ft².

Assumptions to check

  • The surface is rectangular.
  • Waste is applied to the full base area.
  • Irregular cutouts should be measured separately and added or subtracted.

Read the calculation and QA methodology →

Common questions

FAQ

How much waste should I add?

Straight layouts often start near 5–10%. Complex patterns, diagonal cuts, or many corners can require more. Use the value recommended for your material and project.

Can I calculate several rooms?

Calculate each room separately, then add the waste-adjusted areas. This makes unusual shapes and different waste rates easier to review.

Does the calculator round up?

Area results show decimals. Product packaging should be rounded up using the flooring or tile calculator.