Carpet Square Footage Calculator

Measure rooms faster with a simple multi room workflow. Add rectangles L shapes halls and stairs. Toggle feet inches or meters. Apply waste and optional cost. Get live totals in square feet and yards. Export CSV and PDF. Includes examples formulas FAQs and a print ready summary. Save projects locally for easy future edits.

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Rooms & Areas

Room name Shape Dimensions Area (sq ft) Actions
Shapes: Rectangle, L-Shape (two rectangles), Hallway Runner, Stairs (area ≈ steps × (tread + riser) × width; add landings as rectangles).

Formula & Method

This calculator estimates net area and applies a configurable waste allowance to derive a gross purchase quantity.

Rectangles & Hallways
Area = Length × Width
If using meters: ft = m × 3.28084, then compute square feet.
L‑Shape
Split into two rectangles: A = L1 × W1 + L2 × W2
Stairs (treads + risers)
Area ≈ Steps × (TreadDepth + RiserHeight) × StepWidth
Waste & Rounding
Gross = Net × (1 + Waste%).
Square yards: sq yd = sq ft ÷ 9.

Example Data

Click “Load Example” above to auto‑fill rooms below. You can also edit or delete lines after loading.

RoomShapeDimensionsArea (sq ft)
Living RoomRectangle18 ft × 14 ft252
HallwayHallway Runner20 ft × 3 ft60
Primary BedroomL-Shape12×10 + 6×5 ft150
StairsStairs13 steps, 10 in tread, 7 in riser, 3 ft width ~ 70

FAQ

Break the shape into rectangles. For L‑shapes enter two rectangles. Add any landings as separate rectangles. The tool sums everything automatically.

For simple rooms use 5–10%. For complex layouts, pattern repeats, or many seams 10–15% is typical. Very intricate spaces may need 15–20%.

Yes. Provide steps, tread depth, riser height, and width. The tool estimates tread+risers coverage. Add landings as rectangles if needed.

Use the Units toggle. In feet/inches mode each dimension has feet and inches fields. Metric uses meters with automatic conversion to square feet.

Enter your price per square foot. The calculator multiplies it by the gross area after waste to give an approximate material amount.

Yes. Use CSV or PDF export, or the Print button for a clean print‑friendly view.

It’s suitable for residential and light commercial. For complex roll plans and seam placement, use a professional estimator or advanced roll‑planning tools.

Last reviewed:

Totals

Net area 0.00 sq ft
Net area 0.00 sq yd
Gross with waste 0.00 sq ft
Gross with waste 0.00 sq yd
Estimated material $0.00
Data is stored locally in your browser.

Related Tools

  • • Carpet Yardage Calculator
  • • Carpet Waste Calculator
  • • Roll Width Fit Optimizer
  • • Stair Runner Length Calculator

How to measure

  1. Sketch each space. Mark doorways and openings.
  2. Measure longest length and widest width for each rectangle.
  3. Break complex spaces into rectangles; use L‑shape when convenient.
  4. For stairs, note steps, tread depth, riser height, and width; add landings as rectangles.
  5. Enter values and review totals; adjust waste for seams/patterns.

About This Carpet Square Footage Calculator

This tool is designed for homeowners, installers, and estimators who need a fast, transparent way to total carpet coverage across multiple spaces. It accepts rectangles, L‑shapes, hallways, and stairs, then converts everything to square feet and square yards. Results update live as you type, and you can optionally apply a waste allowance to reflect real‑world cuts, seams, and pattern repeats. Export to CSV or PDF for sharing, save a project locally to revisit later, and print a clean summary when you are ready to order.

The calculator follows straightforward geometry. Rectangular rooms use length × width. L‑shaped rooms are handled as two rectangles summed together. Hallways are simple rectangles with a long length and narrow width. Stairs are estimated using a proven tread‑plus‑riser approach: the “depth consumed” by each step is the tread depth plus riser height, multiplied by the stair width and number of steps. Landings are best added as separate rectangles so that the total includes all flat surfaces.

Formulas at a Glance

ShapeFormulaNotes
Rectangle / HallwayArea = Length × WidthUse longest length and widest width. Include closets/alcoves as extra rectangles if helpful.
L‑ShapeArea = L1 × W1 + L2 × W2Split the L into two rectangles that do not overlap.
Stairs (estimate)Area ≈ Steps × (Tread + Riser) × WidthAdd landings as rectangles. Use actual measured width.
Square yardssq yd = sq ft ÷ 9Many carpet prices are quoted per square yard.
Gross areaGross = Net × (1 + Waste%)Waste allows for offcuts, seams, and pattern alignment.

Waste Allowance Guidance

Waste represents the difference between ideal geometry and practical installation. Straight rooms with minimal seams typically need less, while complex layouts, strong patterns, or tight stair turns often require more. Use the slider to test scenarios; the math is always displayed so you can verify how gross area derives from the net.

ComplexitySuggested WasteTypical Examples
Simple5–8%Single rectangle, no pattern, minimal seams
Moderate8–12%Multiple rooms, mild pattern, standard seams
High12–15%Irregular shapes, long hallways, pattern alignment
Very High15–20%Complex layouts, heavy pattern repeats, many transitions

Units, Conversion, and Rounding

You can toggle between feet/inches and meters. When using metric, dimensions are entered in meters and converted automatically: feet = meters × 3.28084. The calculator then computes area in square feet and shows square yards for convenience. If you prefer conservative ordering, consider rounding the gross area up to the next whole square yard, especially when you expect unforeseen offcuts or doorway trims.

ConversionRelationUsage
Meters to feetft = m × 3.28084Used for metric inputs before area math
Square yardssq yd = sq ft ÷ 9Handy for pricing comparisons
Gross with wasteGross = Net × (1 + Waste%)Represents purchase quantity

Workflow Tips and Limitations

Sketch each floor, measure longest length and widest width, and break unusual spaces into rectangles. For stairs, capture steps, tread depth, riser height, and width; add any landings separately. Use the price field to estimate material cost, keeping in mind that taxes, labor, removal, pad, trims, and delivery are not included. The stair method is an estimate; for premium patterns, curved winders, or commercial roll‑planning, consult a professional estimator who can model seam placement against roll widths. Saving your project to the browser lets you return later to refine numbers or create multiple versions for comparison.

Related Calculators

Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.