MathUpdated December 2025

Square Footage Calculator

Calculate the square footage and square meters of any room, lot, or area. Supports rectangles, triangles, circles, L-shapes, and trapezoids in feet, inches, meters, centimeters, and yards.

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Updated 2025

Square Footage Calculator

Use this free square footage calculator to find the area in square feet and square meters for any room or lot.

Rectangle dimensions

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How Square Footage Is Calculated

For real estate

Square footage of a home is the sum of all floor areas at grade level. Basements, garages, and unconditioned spaces often excluded from "living area." Always verify with the listing agent.

For flooring and tile

Add 5-10% for waste and cuts. A 200 sq ft room needs 210-220 sq ft of material. Diagonal layouts or herringbone patterns need 15% extra.

For landscaping

Square footage of a lawn determines how much seed, sod, or fertilizer to buy. Standard rate: 1 lb of grass seed per 1000 sq ft for new lawns, 0.5 lb for overseeding.

For painting

Walls are measured in linear feet \u00d7 height, then multiplied. One gallon covers ~350 sq ft of wall. Subtract windows and doors (each ~15-20 sq ft).

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How our square footage calculator works

1

Choose your shape

Select rectangle, triangle, circle, trapezoid, or sector. Each shape uses the right area formula: length x width for rectangles, pi x r^2 for circles, etc.

2

Enter dimensions

Type dimensions in feet, inches, meters, centimeters, or yards. The calculator converts and computes area in your chosen units.

3

See area in multiple units

Get the result in square feet, square meters, square yards, and acres. Useful for flooring, paint, real estate, and landscaping projects.

Key things to know about our square footage calculator:

  • Flooring and tile: Add 10-15% waste to the measured area to cover cuts and breakage. For diagonal patterns, add 20% waste.
  • Paint coverage: One gallon of paint covers about 350 square feet per coat. Multiply by 2 for two coats, plus 10% waste.
  • Real estate: Square footage calculations in real estate often exclude unfinished basements, garages, and low-ceiling rooms. Check your local MLS rules for the standard.

For related calculations, try our concrete calculator.

FAQ

Frequently asked questions

Everything you need to know about this calculator. Can't find what you're looking for? Email our team.

A square footage calculator is a free tool that finds the area in square feet and square meters for any room, lot, or shape. Our square footage calculator supports rectangles, triangles, circles, L-shapes, and trapezoids in feet, inches, meters, centimeters, or yards. The square footage calculator is used for flooring, paint, landscaping, and real estate.

How it works

How to calculate the square footage of any area

Our square footage calculator lets you find the area in square feet and square meters for rectangles, triangles, circles, L-shapes, and trapezoids, in three steps.

  1. 1

    Pick a shape and unit

    Choose Rectangle, Triangle, Circle, L-Shape, or Trapezoid from the Shape dropdown. Pick the unit you measured in: feet, inches, meters, centimeters, or yards. The result converts to square feet and square meters automatically.

  2. 2

    Enter your measurements

    Type the dimensions of the area. For rectangles, enter length and width. For triangles, enter base and height. For circles, enter radius. For L-shapes, enter both outer rectangles. For trapezoids, enter both bases and the height.

  3. 3

    Read the result

    The result shows square feet, square meters, and the perimeter. Use the area for flooring, paint, landscaping, or real estate listings. Use the perimeter for trim, fencing, or border materials. The share button creates a link with your inputs filled in.

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