Square Foot Calculator
Free square footage calculator for 11 shapes with instant unit conversion
Overview
Square Foot Calculator is a free web tool that computes the area of any space and returns results at once in square feet, square inches, square yards, square meters, and acres. It supports 11 shapes (rectangle, square, circle, triangle, trapezoid, annulus, L-shape, cathedral wall and more) and accepts input in feet, inches, yards, meters or centimeters with automatic conversion. You can add a material waste factor and estimate total project cost from a price per unit, making it ideal for flooring, tiling, painting and landscaping planning.
Our take
A free square footage calculator covering eleven shapes with unit conversion, requiring no account. It is a small utility that does one thing correctly, which is exactly what this category should be. The arithmetic is deterministic, so accuracy depends on your measurements rather than on the tool.
Worth it if
Flooring, paint, carpet and renovation estimates where you need area from measurements.
Look elsewhere if
Official property measurement, which follows defined standards rather than simple geometry.
✨ Features
11 Shape Presets
Calculate area for rectangles, circles, triangles, trapezoids, L-shapes, cathedral walls and more.
Multi-Unit Output
See results simultaneously in square feet, inches, yards, meters and acres.
Waste Factor
Add a surplus percentage so you order enough material without running short.
Cost Estimation
Enter a price per unit to get an instant total project cost.
⚖️ Pros & Cons
Pros
Cons
💰 Pricing
Free
$0
- All 11 shape calculators
- Every unit conversion included
- Waste factor and cost estimator
- No signup, no paywall
Categories
❓ Frequently Asked Questions
Does this match official property square footage?
Not necessarily. Property measurement follows defined standards — ANSI Z765 in the US, RICS elsewhere — that specify what counts as living area, how to treat sloped ceilings, stairwells and unfinished space. Geometric area from your own measurements is useful for materials and not for listings or valuations.
How much extra material should I order?
Usually ten percent above calculated area for straightforward rooms, more for diagonal layouts, patterned materials that need matching, or rooms with many cuts. Calculated area is the minimum; waste from cuts is what determines what you actually need to buy.