Square Footage Calculator

Calculate square footage for rooms, flooring, painting, and landscaping projects.

ft
ft
Total Area
180 sq ft
16.72 m² · 20 sq yd

How to Calculate Square Footage

Area = Length × Width

For rectangular spaces, simply multiply length by width. For irregular shapes, divide the area into rectangles, calculate each separately, then add the results.

Common Room Sizes

Room SizeSquare FeetSquare Meters
10 × 101009.29
12 × 1214413.38
12 × 1518016.72
15 × 2030027.87
20 × 2040037.16

Waste Factor Guide

MaterialRecommended Waste
Flooring (tile, hardwood)10–15%
Paint10%
Carpet5–10%
Wallpaper15–20%

Frequently Asked Questions

How do I calculate square footage?
Multiply length by width. For a room that's 12 feet by 15 feet: 12 × 15 = 180 square feet. For irregular shapes, break the area into rectangles, calculate each, and add them together.
How many square feet is a 12x12 room?
A 12×12 room is 144 square feet (12 × 12 = 144). This is a common bedroom or living room size.
How do I calculate square footage for flooring?
Measure the length and width of each room, multiply to get square feet, then add 10% for waste and cuts. For 180 sq ft, order at least 198 sq ft of flooring.
How do I convert square feet to square meters?
Multiply square feet by 0.092903. For example, 200 sq ft × 0.092903 = 18.58 square meters. Or use our unit converter.
How do I measure a room with multiple areas?
Break the room into separate rectangles. Measure each section's length and width, calculate each area, then add them together. This calculator supports multiple areas.

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