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Carpet Calculator
Estimate carpet area from room length, room width, and optional waste allowance.
Enter your dimensions
Current unit: feet. The estimate updates automatically in your browser.
Enter the room length.
Enter the room width.
Optional extra allowance for trimming, fitting, and ordering margin.
Estimated result
Carpet needed
Enter your inputs
Your estimate will appear here automatically once the required inputs are valid.
Guide
How to use this estimate
How the carpet calculator works
This calculator multiplies room length by room width to estimate floor area, then adds the optional waste allowance. In imperial mode, the primary result is shown in square feet, with square yards shown as the equivalent value.
It is an area estimate, not a roll layout or seam planner. Carpet roll width, seam placement, stairs, pattern direction, and installer rules can change the final ordering quantity.
What to measure
Measure the room length and room width. For a simple rectangular room, those two numbers are enough to estimate the base carpet area.
Enter a waste allowance if you want an ordering margin for trimming and fitting. For complex rooms, stairs, or patterned carpet, confirm the final quantity with the installer or supplier.
Example carpet calculation
- Room length: 12 feet
- Room width: 10 feet
- Base area: 12 × 10 = 120 square feet
- Waste allowance: 10%
- Adjusted area: 120 × 1.10 = 132 square feet
- Square yards equivalent: 132 ÷ 9 = 14.67 square yards
Estimated carpet needed: 132 square feet, equivalent to 14.67 square yards.
Quick reference
| Item | Value | Note |
|---|---|---|
| Basic formula | Length × width × (1 + waste %) | Adds optional waste allowance to measured floor area. |
| Imperial output | Square feet | The calculator also shows square yards as an equivalent value. |
| Metric output | Square meters | Metric mode also shows square yards as an equivalent value. |
Common mistakes to avoid
- Measuring only one side of the room.
- Forgetting waste for trimming and fitting.
- Treating this as a seam or roll-width layout plan.
Frequently asked questions
Why does imperial mode show square feet first?
Most users measure rooms in feet, so square feet is easier to verify from length and width. The calculator also shows square yards because carpet may be quoted that way by some suppliers.
Does this calculate carpet roll width or seams?
No. This is an area estimate only. Roll width, seams, stairs, pattern direction, and installer layout rules can change the final ordering quantity.
How much waste should I add?
Simple rectangular rooms may need a smaller allowance, while complex rooms, stairs, and patterned carpet may need more. Confirm with your installer or supplier before ordering.