Carpet Calculator
Free Carpet Calculator for construction. Enter project dimensions to estimate materials, costs, and requirements.
Formula
Square Yards = (Length × Width / 9) × (1 + Waste %)
Calculate area in square feet, divide by 9 for square yards (industry standard), and add waste factor for cuts and seams.
Worked Examples
Example 1: Master Bedroom Carpet
Problem:15×12 ft bedroom, quality nylon carpet, standard 10% waste.
Solution:Room area:\n15 × 12 = 180 sq ft\n\nConvert to square yards:\n180 ÷ 9 = 20 sq yds\n\nWith 10% waste:\n20 × 1.10 = 22 sq yds\n\nCost (mid-range @ $35/yd carpet):\nCarpet: 22 × $35 = $770\nPadding: 22 × $8 = $176\nInstall: 22 × $6 = $132\nTotal: $1,078
Result:22 square yards | $1,078 installed
Example 2: Large Living Room
Problem:20×18 ft living room, premium carpet, 15% waste for alcove.
Solution:Area:\n20 × 18 = 360 sq ft\n\n360 ÷ 9 = 40 sq yds\n\nWith 15% waste (alcove):\n40 × 1.15 = 46 sq yds\n\nCost (premium @ $45/yd):\nCarpet: 46 × $45 = $2,070\nPadding: 46 × $10 = $460\nInstall: 46 × $6 = $276\nTotal: $2,806
Result:46 square yards | $2,806
Example 3: Multiple Room Project
Problem:Bedroom 12×12, hallway 15×3, closet 6×4, budget carpet.
Solution:Bedroom: 144 sq ft ÷ 9 = 16 sq yds\nHallway: 45 sq ft ÷ 9 = 5 sq yds\nCloset: 24 sq ft ÷ 9 = 2.7 sq yds\n\nSubtotal: 23.7 sq yds\n\nWith 12% waste (transitions):\n23.7 × 1.12 = 26.5 → 27 sq yds\n\nCost (budget @ $25/yd):\nCarpet: 27 × $25 = $675\nPadding: 27 × $6 = $162\nInstall: 27 × $6 = $162\nTotal: $999
Result:27 square yards total | $999
Frequently Asked Questions
How do I calculate carpet needed for a room?
Measure room length and width in feet. Multiply for square feet. Divide by 9 to convert to square yards (carpet is sold by sq yd). Add waste factor: 10% for standard room, 15-20% for stairs or complex layouts, 12-15% for multiple rooms. Example: 15×12 ft room = 180 sq ft ÷ 9 = 20 sq yds + 10% waste = 22 sq yds needed. For multiple rooms, calculate each separately then sum the totals. Odd-shaped rooms: Break into rectangles, calculate each section, sum together. Always verify units when getting quotes - some retailers quote sq ft to appear cheaper.
How much waste should I add for carpet?
Standard room (rectangular, no obstructions): 10% waste for cuts and seams. Large room/minimal seams/simple shape: 5-7% acceptable for experienced installer. Multiple connected rooms/complex layout: 15-20% (more seams, more cuts). Stairs: 15-20% (angle cuts create waste, precise measurements needed). Patterned carpet: 15-25% (must match pattern at seams, increases waste). Hallways and transitions: 10-15%. Never order exact calculated amount - impossible to patch later if damaged. Keep leftover carpet remnants - useful for closets, future patches, or even pet beds. Better to have 1-2 extra sq yds than be short and unable to match dye lot.
What about carpet padding - is it really necessary?
Always use carpet padding - it extends carpet life 50-100%. Padding benefits: Cushioning (comfort underfoot), insulation (warmer floors, sound dampening), protection (absorbs impact, extends carpet life), moisture barrier (some types). Padding types: Foam: Cheapest ($0.30-0.60/sq ft), adequate for light traffic. Rubber: Best quality ($0.80-1.50/sq ft), longest life, great resilience. Fiber/felt: Mid-range ($0.50-1.00/sq ft), good density. Thickness: 1/4\" to 1/2\" (3/8\" standard residential - don't go thicker or carpet gets too soft and wrinkles). Budget rule: Good padding under cheap carpet performs better than cheap padding under expensive carpet. Padding typically 20-30% of carpet cost but critical for longevity.
How much does carpet cost per square foot installed?
Total installed costs (materials + padding + installation): Budget carpet: $3-6 per sq ft ($27-54/sq yd). Mid-range: $6-11 per sq ft ($54-99/sq yd). High-end: $11-20 per sq ft ($99-180/sq yd). Breakdown for mid-range: Carpet: $2-5/sq ft, Padding: $0.50-1.00/sq ft, Installation: $1-2/sq ft, Removal of old: $0.50-1/sq ft, Furniture moving: $0.10-0.25/sq ft. 300 sq ft room typical: Budget $900-1,800, Mid-range $1,800-3,300, High-end $3,300-6,000. Stairs add $40-80 per step. Always get 3 quotes - prices vary significantly. Watch for bait-and-switch on advertised low prices.