Carpet Calculator
Find out how much carpet you need in square feet, square yards, and linear feet. Built-in seam logic for rooms wider than the standard 12-foot broadloom roll.
10% typical; 15% for patterned carpet or stairs.
Results
Carpet is priced per square yard in the US. Multiple strips need seaming — ask the installer to plan seams away from high-traffic areas and natural light.
Why Carpet Math Is Different
Carpet behaves differently from tile or hardwood because it comes off a roll in fixed widths, not in identical units like planks or tiles. Most US broadloom carpet is 12 feet wide. If your room is wider than the roll, you need a seam — and seams are something a thoughtful installer plans carefully.
Roll width matters more than total area. A 13 × 16 ft room can be carpeted with a single strip from a 13.5 ft roll, but the same 13 × 16 ft area with a 12 ft roll needs two strips and a seam. The wider roll is often the better buy even if the per-yard price is slightly higher.
Pile direction is one-way. All carpet strips in a room should run in the same direction so the pile catches light identically. This rule dictates strip orientation and sometimes increases waste.
Carpet Cost in 2026
US carpet pricing as published by The Home Depot, Lowe's, and major flooring chains:
- Builder-grade nylon: $1–3 per sq ft material, $3–6 installed.
- Mid-range plush or Berber: $3–6 per sq ft material, $6–9 installed.
- Premium wool or solution-dyed nylon: $6–12 per sq ft material, $10–15 installed.
- Carpet pad: $0.30–1.00 per sq ft, recommended on every install.
Always confirm if installation includes tear-out, haul-away, and tack strip — these can add $0.50–1.50 per sq ft.
How to Calculate Carpet Needed in 5 Steps
- Measure the room. Record length and width at the longest points in feet.
- Calculate raw area. Multiply length × width to get square feet.
- Choose a roll width. Common widths are 12 ft, 13.5 ft, and 15 ft. Wider rolls reduce seams but may cost more per yard.
- Plan seams and strips. If the room is wider than the roll, calculate how many full strips you need and where the seam will fall.
- Add waste. Plain carpet needs 10% waste; patterned or directional carpet needs 15–20%.
Carpet Type Comparison
| Carpet Type | Durability | Material Cost | Best For |
|---|---|---|---|
| Nylon | Excellent | $2–6 / sq ft | High-traffic homes, pets |
| Polyester | Good | $1–4 / sq ft | Budget rooms, low traffic |
| Olefin | Moderate | $1–3 / sq ft | Basements, moisture-prone areas |
| Wool | Very good | $6–15 / sq ft | Luxury spaces, allergies (natural) |
| Berber | Excellent | $2–7 / sq ft | Heavy traffic, hiding dirt |
Waste Allowance by Carpet Pattern
| Pattern / Style | Waste Allowance | Why |
|---|---|---|
| Solid / Textured | 10% | Minimal matching; only cuts and seams |
| Plush / Saxony | 10–12% | Pile direction must be consistent |
| Berber / Loop | 10–15% | Pattern rows must align at seams |
| Floral / Geometric | 15–20% | Pattern repeat must match across seams |
| Stairs | 15% | Extra cuts at riser-tread transitions |
Seam Planning Tips
Place seams away from traffic. A seam running across a hallway or doorway will wear faster and be more visible.
Run seams parallel to the longest wall. This usually minimizes the number of strips and total seam length.
Avoid seams in natural light. Sunlight across a seam can make even a good installation visible. Place seams where light falls evenly.
Patterned carpet needs larger repeats. When matching pattern repeats, add the pattern repeat distance to every strip beyond the first.
Frequently Asked Questions
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Sources
The figures on this page are based on data from these authoritative industry sources.
- The Home Depot Buyer’s Guides — Retail price ranges for flooring, paint, and finishing materials.