Square Footage Calculator

Add Room(s)

Cost Per Square Foot ($) - optional

Total Square Footage

0 sq ft

Breakdown by Room

Area Formulas by Shape

Rectangle / Square

Area = Length × Width

Circle

Area = π × Radius² (Radius = Diameter ÷ 2)

Triangle

Area = (Base × Height) ÷ 2

Unit Conversion

Square Meters = Square Feet × 0.092903
Square Feet = Square Meters ÷ 0.092903

Frequently Asked Questions

For a rectangular room, multiply length by width, both measured in feet: Square Footage = Length (ft) × Width (ft). For an L-shaped room, split it into two rectangles, calculate each separately, then add them together.

Multiply square feet by 0.092903 to get square meters, or divide square meters by 0.092903 to get square feet. For example, 1,000 sq ft = 1,000 × 0.092903 ≈ 92.9 square meters.

Real estate listings typically use square footage to describe the total livable, heated/cooled interior space of a home, generally excluding garages, unfinished basements, and porches (standards vary by region and appraiser). Square footage is also the basis for price-per-square-foot comparisons between similar homes in a market.

Break the irregular shape into simpler shapes you can measure separately - rectangles, triangles, or circles/half-circles - calculate the area of each piece, then add them together for the total. This calculator lets you add multiple room sections and shapes, then sums them into one total.

Square Footage Calculator - Measure Any Room or Irregular Space

Square footage is the basis for nearly every home-related calculation - flooring, paint, real estate pricing, HVAC sizing, and renovation budgets all start with an accurate area measurement. This calculator handles rectangular, circular, and triangular spaces individually and lets you add multiple sections together, which is exactly how professionals measure irregularly shaped rooms.

Basic formula: Rectangle Area = Length × Width
Unit conversion: 1 sq ft ≈ 0.0929 sq meters

Measuring Irregular Rooms

Most real rooms aren't perfect rectangles - L-shaped living rooms, rooms with bay windows, or open floor plans with alcoves are common. The standard approach is to mentally (or physically) divide the space into simpler shapes - rectangles, triangles, or circle segments - measure each one, then add the areas together. This calculator's "add another room" feature is built for exactly this: add each section as you measure it, and the tool sums the total automatically.

Square Footage in Real Estate

When shopping for or selling a home, square footage is often the single number used to compare properties and calculate price per square foot. However, standards for what counts (finished basements, garages, screened porches) vary between appraisers, real estate agents, and local building codes - always clarify what's included when comparing listings, and consider verifying a listed square footage independently for an important purchase.

How this calculator works, and where the numbers come from

The Square Footage Calculator applies the standard formula for this calculation to the values you enter and updates the result as you type. The calculation itself happens in your browser, and the page explains the method so you can check any result by hand.

Please note: Results are estimates. Lender terms, local taxes and fees vary, so confirm figures with your lender or a qualified adviser.

Sources and further reading

Learn more

Read our guide: How Much Paint, Flooring and Concrete Do You Actually Need?

Last reviewed: October 6, 2026 by the CalcQube Editorial Team. See our editorial policy for how we build and check calculators, or report an error.