Square Footage Calculator
Enter the length and width of a room, wall, floor, yard, or project area. Use the unit switch if you want metric inputs and results.
Last updated: May 2026
Buying and sizing notes
- Round up when buying materials sold in full pieces, rolls, boxes, bags, or bundles.
- For rooms with closets, alcoves, or jogs, measure each section separately for better accuracy.
How to use this estimate
What this includes
- The required inputs shown on this page
- common planning assumptions
- optional advanced adjustments where provided
What it does not include
- site-specific professional design
- local code approval
- manufacturer-specific requirements
- installation quality
Common mistakes
- Leaving a required input at the default when your situation is different
- ignoring product labels or ratings
- treating the estimate as an exact final answer
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