Carpet Calculator
Calculate how many square yards of carpet and padding to buy for any room. Get an order summary with optional cost estimates.
Last updated: April 12, 2026
Enter Room Size
Order Summary
Worked examples
12×12 Bedroom
144 sq ft room · 10% waste · textured carpet · standard padding
This is a straightforward order. The room fits within a 12-foot roll width, so no extra seam material is needed beyond the 10% waste allowance.
12×15 Living Room
180 sq ft room · 10% waste · frieze carpet · premium padding
A common living room size. The 15-foot width still fits within a 12-foot roll with one seam along the length. The 10% waste covers the seam cut.
14×14 Room (wider than roll)
196 sq ft room · pattern carpet · same-direction nap
When the room is wider than the 12-foot roll AND the carpet has a pattern or direction requirement, you may need nearly double the material. Always ask the supplier about remnants or partial rolls.
Carpet Roll Width: Why It Matters
Carpet is sold in standard 12-foot wide rolls. When your room exceeds that width, you need seams—and the amount of extra material depends on whether the carpet has a pattern or directional nap.
Carpet is manufactured in 12-foot wide rolls. Some brands offer 13'6" or 15' widths, but 12' is the default you will see at most retailers.
If your room is 12 feet wide or less, you only need length plus waste. One continuous piece covers the floor with a single seam at the edges.
When the room exceeds the roll width, you need multiple lengths joined with seams. The nap or pattern direction determines whether you can mix directions or must buy extra length to match.
Many suppliers sell partial rolls or remnants at a discount. If your room needs a small additional piece, you may not need to buy a full second length.
How Much Waste to Add
| Project type | Waste | Why |
|---|---|---|
| Standard rectangular room | 5–10% | A simple rectangle under 12 feet wide usually stays within 5–10%. Add 10% for a safe default. |
| L-shaped or irregular room | 15% | More cuts and corners mean more waste. Break the room into rectangles and sum them, then add 15%. |
| Stairs | 15–20% | Each tread and riser is a separate cut. Stair carpet is usually measured separately or by an installer. |
| Pattern or directional carpet | Can exceed 50% | If the nap or pattern must align, rooms wider than 12' may need extra length to match seams. Ask the supplier before ordering. |