Carpet Calculator
Carpet Coverage Reference Chart
Square yards needed by room size (no seam allowance).
| Room Size | Sq Ft | Sq Yards | 12' Roll (linear ft) |
|---|---|---|---|
| 10' × 10' | 100 | 11.1 | 10' |
| 10' × 12' | 120 | 13.3 | 10' |
| 12' × 12' | 144 | 16.0 | 12' |
| 12' × 15' | 180 | 20.0 | 15' |
| 15' × 15' | 225 | 25.0 | 15' |
| 15' × 20' | 300 | 33.3 | 20' |
| 20' × 20' | 400 | 44.4 | 20' |
How We Calculate This
This carpet calculator uses established formulas and industry-standard data to provide accurate estimates.
- Enter your specific values into the calculator fields above
- Our algorithm applies the relevant formulas using your inputs
- Results are calculated instantly in your browser — nothing is sent to a server
- Review the detailed breakdown to understand how each factor affects your result
These calculations are estimates based on standard formulas. For critical decisions, always consult a qualified professional.
How to Convert Oven Recipes to Air Fryer
Carpet is sold by the square yard (or linear foot off a roll). The key is matching your room dimensions to the roll width to minimize seams and waste.
The basic rule:
- Measure room length and width — round up to the nearest 3 inches for a snug fit
- Choose a roll width (12' or 15') that minimizes seams — if your room is 13' wide, a 15' roll avoids seams entirely
- Factor in seam allowances (3-6 inches per seam) and pattern matching if your carpet has a repeating pattern
Carpet padding is essential and sold separately — it adds comfort, insulation, and extends carpet life. Standard pad thickness is 7/16" for most residential applications. Plan for the same square footage of padding as carpet, plus a little extra for overlap at seams.
When Would You Use This Calculator?
This carpet calculator is designed for anyone who needs quick, reliable estimates without complex spreadsheets or professional consultations.
- When you need a quick estimate before committing to a purchase or project
- When comparing different options or scenarios side by side
- When planning a budget and need to understand potential costs
- When you want to verify a quote or estimate you've received from a professional
- When teaching or learning about the concepts behind these calculations
Frequently Asked Questions
How do I convert square feet to square yards for carpet?
Divide square feet by 9. For example, a 12×15 room is 180 sq ft ÷ 9 = 20 square yards. Carpet is priced by the square yard, so this conversion is essential for budgeting. Remember to add waste before converting.
What's the difference between 12-foot and 15-foot carpet rolls?
The number refers to the roll width. A 12' roll is the most common and cheapest option. A 15' roll costs slightly more but can cover wider rooms without seams. If your room is 13' wide, a 12' roll requires a seam, while a 15' roll covers it seamlessly. Fewer seams mean a better-looking, longer-lasting installation.
How much does carpet installation cost?
Carpet material costs $10-$80 per square yard ($1-$9 per sq ft). Professional installation adds $3-$6 per square yard for labor. Pad costs $3-$8 per square yard. For a 200 sq ft room, budget $400-$1,800 total for material, pad, and installation. Many retailers offer free installation promotions.
How much extra carpet should I order?
Order 10% extra for rectangular rooms with few obstacles. For L-shaped rooms, stairs, or rooms with many doorways, order 15-20% extra. Carpet waste comes from matching the roll width to your room dimensions and from seam allowances. Keep leftover carpet for future repairs.
How long does carpet last?
Quality carpet lasts 10-15 years in active households, up to 20+ years in low-traffic areas. Nylon fiber is the most durable (12-15 years), polyester is mid-range (5-10 years), and olefin/polypropylene is budget-friendly but less durable (3-5 years). Regular vacuuming and professional cleaning every 12-18 months extend carpet life significantly.
Do I need carpet padding?
Yes, carpet padding is essential. It provides cushion underfoot, absorbs sound, insulates against temperature, and extends carpet life by absorbing impact that would otherwise wear the carpet backing. Standard residential pad is 7/16" thick with 6-8 lb density. Thicker is not always better — too-thick pad can cause carpet to buckle.