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Carpet Calculator

By Muhammad Abdullah Rauf · Founder, EverydayTools.proUpdated 2026-06-27

How much carpet do I need for a room?

Carpet quantity is **floor area × (1 + waste%)**, converted to **square yards** (÷ 9). Linear feet depend on roll width and strip layout.

**Formula:**

Sq ft to order = Net floor sq ft × (1 + waste% / 100)

Sq yd = Sq ft to order ÷ 9

Strips = ceil(short wall ÷ roll width)

Linear ft = strips × long wall × (1 + waste%)

**Example — 12×12 ft, 12 ft roll, 10% waste:**

158.4 sq ft → **17.6 sq yd**, **1 strip**, **13.2 linear ft**

Carpet square yard and strip layout

Net floor area times waste buffer, converted to sq yd; strips from roll width.

Formula

sq_yd = (net_sq_ft × (1 + waste%)) / 9; strips = ceil(short_wall / roll_width)

Assumptions

  • Roll width matches supplier broadloom (typically 12 ft).
  • Seams run parallel to longest wall.

Limitations

  • Does not calculate pad, tack strip, or transition metal.
  • Pattern match beyond waste preset needs manual adjustment.

How to use Carpet Calculator

  1. Pick a room preset

    Tap 12×12 bedroom, 15×20 living, or enter floor sq ft on the main form.

  2. Enter roll width

    12 ft is standard broadloom — 15 ft rolls reduce seams on wide rooms.

  3. Set waste buffer

    10% for cut-pile; 15% for pattern carpet that must match at seams.

  4. Read sq yd and linear ft

    Results show carpet to order, strips, linear feet, and purchase guide.

  5. Pair with flooring

    Use Flooring Calculator for hard surfaces in adjacent rooms.

Carpet Calculator examples

144 sq ft · 10% · 12 ft roll

Input

12×12 room

Output

17.6 sq yd

158.4 sq ft ÷ 9 = 17.6 sq yd.

300 sq ft · 10%

Input

15×20 living

Output

~36.7 sq yd

330 sq ft ÷ 9 = 36.67 sq yd.

500 sq ft area mode

Input

Open plan

Output

~61.1 sq yd

550 sq ft with 10% waste ÷ 9.

40 sq ft hall

Input

Runner area

Output

~4.9 sq yd

44 sq ft ÷ 9 with 10% waste.

Who uses Carpet Calculator?

Common real-world scenarios where this tool saves time.

12×12 bedroom

144 sq ft + 10% waste ≈ 17.6 sq yd on 12 ft roll.

15×20 living room

300 sq ft — two strips across 15 ft width.

Pattern carpet

Use 15% waste preset — pattern must align at seams.

Workflow guides

Step-by-step chains that connect related tools for common tasks.

Carpet a bedroom

  1. Measure 12×12 or enter floor sq ft.
  2. 12 ft roll, 10% waste, plush preset.
  3. Order from one dye lot; power-stretch install.
  4. Estimate wall paint for same room. Paint Calculator

Reference tables

Recommended waste by carpet type

TypeWaste %
Cut-pile / plush10%
Berber loop10%
Pattern / print15%

Sq yd from room size (10% waste)

RoomSq yd
12×12 (144 sq ft)17.6
15×20 (300 sq ft)36.7
20×20 (400 sq ft)48.9

Best practices

Power-stretch install

Match dye lot

Common mistakes to avoid

Ordering by sq ft instead of sq yd

Carpet is priced per **square yard** — divide sq ft by 9.

Ignoring roll width

Seams depend on roll width — 12 ft roll on a 15 ft wide room needs two strips.

Mixing dye lots

Shade varies between production runs — buy all carpet at once.

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Frequently Asked Questions

How much carpet do I need for a 12×12 room?

144 sq ft floor. With 10% waste (158.4 sq ft): about 17.6 square yards on a 12 ft roll.

How do I convert carpet sq ft to sq yd?

Divide square feet by 9. Example: 158.4 sq ft ÷ 9 = 17.6 sq yd.

What is standard carpet roll width?

12 ft is most common broadloom. Some suppliers offer 15 ft rolls for fewer seams.

How much extra carpet should I buy?

10% for cut-pile and berber; 15% for pattern carpet that must match at seams.

How many linear feet of carpet?

Strips × longest wall, with waste. A 12×12 room on 12 ft roll = 1 strip × 12 ft = 12 linear ft (plus waste).

Carpet vs LVP flooring?

Use Flooring Calculator for vinyl plank or laminate — different waste and carton math.

Do I need carpet pad?

Pad is sold separately — this calculator covers broadloom only, not pad sq yd.

Can I use this for carpet tiles?

Carpet tiles use box counts like flooring — use Flooring Calculator with tile carton sizes.

How do I measure for carpet?

Length × width inside walls for each room. For area mode, enter total sq ft directly.

Why buy from one dye lot?

Color shifts between production batches — ordering all at once avoids visible seams.

Privacy, accuracy, and trust

Privacy

Room dimensions stay on your device — no upload to EverydayTools servers.

Estimates only — verify with your carpet retailer for pattern match and roll availability.

Part of Calculator Tools

More free tools for the same workflow.

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Reviewed on 2026-06-27.