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Carpet Calculator

Calculate carpet — order yd², linear ft, strips, room ft², offcuts ft², cost with waste for US coverage. Enter dimensions, select units and add waste to get instant, supplier-ready numbers.

1. Measurements & Dimensions

2. Material Properties & Waste Allowance

3. Optional Material Cost

CARPET CALCULATOR ESTIMATE
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Enter dimensions above to calculate

Calculation Breakdown & StepsFormula: Strips = ceil(room width / roll width); purchased length = strips × room length × allowance factor; purchased area = purchased length × roll width.
  1. Enter values to see step-by-step substitution.

    Engineering Assumptions:

    • All strips run along the entered room length, with no reuse of offcuts. Swap room length and width to compare seam direction.
    • Pattern repeat, pile direction, seams and irregular alcoves may require additional stock. Price applies to the full roll area purchased, not just room area.
    VISUAL GUIDE — CARPET CALCULATORflooring · carpet-calculator

    TOP VIEW — Length × Width

    Carpet Calculator topLength 10ftWidthCarpet10×15 = 150 ft²

    SECTION — Carpet roll width 3ft

    Carpet Calculator sectionCarpet 3ft3"Strips = ceil(room width / roll width); purchased length = strips × room length × allowance factor; purchased area = purchased length × roll width. · +10% → 1.53 yd³
    Carpet Calculator — Strips = ceil(room width / roll width); purchased length = strips × room length × allowance factor; purchased area = purchased length × roll width. · example 10×15 @3ft = 37.5 ft³ (1.39 yd³) → 1.53 yd³ with 10% waste · carpet-calculator

    What Is This Calculator?

    The Carpet Calculator — Covers US floors — hardwood, laminate, vinyl, carpet and tile with grout and waste.

    What Does It Calculate?

    • Floor area in square feet
    • Boxes or rolls with waste
    • Grout and adhesive

    How to Use the Calculator

    1. Measure Room 12x10 ft, 12 ft roll — use feet for length/width and inches for thickness where typical.
    2. Enter values and select units. The calculator converts to feet before calculating (inches /12, yards x3).
    3. Adjust waste % and optional price, then click Calculate. Results show with waste included.
    4. Use Reset to clear and try another size.

    Formula & Engineering Methodology

    Strips = ceil(room width / roll width); purchased length = strips × room length × allowance factor; purchased area = purchased length × roll width.

    • Area — Length*Width
    • Roll — 12 ft wide standard

    All units convert to exact standard engineering dimensions (NIST SP 811) before calculation to ensure consistency between US Customary and Metric measurements.

    Worked Example

    Example: Room 12x10 ft, 12 ft roll

    STEPVALUE
    Strips10 ft width /12 ft roll = 1 strip
    Length12 ft *1 = 12 ft = 4 yd
    With waste4.4 yd

    Construction Information

    Material: Tile 12x12 in = 1 ft2, 6.8 per ft2 with grout. Hardwood 20 ft2 per box. Carpet 12 ft wide rolls.

    Carpet rolls 12 ft wide, seam in middle for >12 ft. Add 10% pattern waste.

    Material Information

    Tile 12x12 in = 1 ft2, 6.8 per ft2 with grout. Hardwood 20 ft2 per box. Carpet 12 ft wide rolls.

    Waste & Overages

    Add 10% for straight, 15% for diagonal or large tile. Pattern adds 20%.

    Practical Tips

    • Acclimate wood 72 hours
    • Stagger joints 6 in

    Common Mistakes

    • Not adding waste for diagonal — short 15%
    • Forgetting grout joint — count off

    Assumptions & Engineering References

    • All strips run along the entered room length, with no reuse of offcuts. Swap room length and width to compare seam direction.
    • Pattern repeat, pile direction, seams and irregular alcoves may require additional stock. Price applies to the full roll area purchased, not just room area.

    This calculator provides an estimate based on your inputs. Actual requirements vary by site, material and installation. For code-regulated or load-bearing work, consult a qualified professional.

    Calculations run 100% in your browser — zero tracking of your dimensions or input data.

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    Frequently asked questions

    What does the Carpet Calculator calculate?

    The Carpet Calculator estimates carpet quantity for US jobs — Floor area in square feet, Boxes or rolls with waste, Grout and adhesive. Enter dimensions, choose units, add waste and price to get instant results.

    How do I measure for carpet?

    Measure room 12x10 ft, 12 ft roll on site. Use the unit selectors — the tool converts inches→feet (÷12) and yards→feet (×3) before math. For non-rectangular, split into rectangles and add.

    How much waste should I add?

    Add 10% for straight, 15% for diagonal or large tile. Pattern adds 20%.

    How accurate is this carpet estimate?

    Math is exact for your inputs. Actual needs vary by site, material and installation. Add 5–10% waste for rectangular, 10–15% for irregular.

    About Calculator Street

    Built by Vipul Otari for US homeowners & contractors. Calculator inputs are processed in your browser. Estimates depend on your measurements, product specifications and the assumptions shown on this page. Confirm order quantities with your supplier and structural requirements with your project designer. Page updated: 2026-09-11.

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