Area Calculator · Practical guide
How to Measure a Room for Flooring
Length × width gives your square footage; add 10% for cuts and waste before you order.
At a glance
The Basic Method
Measure the room's length and width in feet, then multiply: that product is the square footage of flooring you need. A 12 × 15 foot room is 180 ft², and with the standard 10% waste allowance you should order about 198 ft² of material.
Interactive tool
Area Calculator
Enter your own values, then compare the result with the examples below.
Results
Formula Used:
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Step by Step
- Measure wall to wall at the longest point in each direction, in feet.
- Multiply length × width for the main rectangle.
- Measure closets, alcoves, and bay areas separately and add their areas.
- Multiply the total by 1.10 to cover cuts, mistakes, and future repairs.
Handling Odd Shapes
Split non-rectangular rooms into rectangles, triangles, or half-circles and add the pieces. An L-shaped room 10 × 12 overall with a 4 × 6 notch becomes 60 ft² + 36 ft² = 96 ft². A curved entryway can be treated as a half-circle: ½πr², so a 4-foot radius curve adds about 25.1 ft².
Measuring in Feet and Inches
Convert inches to decimal feet before multiplying: divide the inches by 12. A room that measures 12 ft 6 in by 14 ft is 12.5 × 14 = 175 ft². The calculator accepts decimals, so you can enter 12.5 directly and get the exact area.
Frequently Asked Questions
How much extra flooring should I order?
Add 10% for a standard straight-lay installation. Bump that to 15% for diagonal layouts, herringbone patterns, or rooms with many corners.
Do I measure wall to wall or baseboard to baseboard?
Measure wall to wall. Flooring runs under the baseboards, so the full wall-to-wall dimension is the correct one.
How do I convert my measurements if I measured in inches?
Divide inches by 12 to get decimal feet. 150 inches is 12.5 feet. Then multiply the two decimal-foot dimensions to get square feet.
Should I subtract the area of kitchen islands or cabinets?
Yes, if flooring will not run underneath them. Measure the footprint of any fixed cabinet or island and subtract it from the room total.