RightQty

Exterior materials

Siding calculator

Estimate general siding coverage from repeated walls, triangular gables, openings, waste, and optional exact product coverage without assuming one panel format.

General exterior coverage

Calculate siding quantity

Measurement system
Optional equal gablesTriangular area
Optional product coverageAdds whole-piece output
Copy usable coverage from the exact product.
Overage

Covers spillage, uneven depth, settling, and minor measurement differences.

Optional material costEnter your supplier's USD price

Material only; taxes, delivery, fasteners, accessories, installation, and labor are excluded.

No signup. Your measurements stay in your browser.

Your material estimate

Siding coverage to order

286sq ft

Includes 10% overage and purchase-unit rounding where applicable.

Gross wall and gable area
300 sq ft
Openings deducted
40 sq ft
Net siding area
260 sq ft
Waste-adjusted siding area
286 sq ft
Waste-adjusted siding squares
2.86 squares

Example estimate: default sample values are shown. Update the measurements and select Calculate before using or copying this list.

Take this to your supplier

Shopping list

  • Siding coverageConvert this coverage to the exact product packaging supplied by the manufacturer.286 sq ft
  • Siding coverage in squaresOne siding square is 100 square feet.2.86 squares
Calculation assumptions
  • Equal wall sections repeat the entered rectangular width and height; gables are repeated triangles.
  • Openings are subtracted exactly as entered before the waste allowance.
  • Coverage per piece is optional and must come from the selected product; no universal panel size or exposure is assumed.
  • Accessories, layout cuts, fastening, weather barriers, structural suitability, and code compliance are not inferred.

Planning guidance

Measure and choose assumptions before calculating

Material-neutral area math

How siding quantity is calculated

1

Gross exterior area

(wall width × height × count) + (gable base × height ÷ 2 × count).

2

Net and adjusted area

Subtract entered openings, then apply the selected waste percentage.

3

Purchase units

Report area and 100-square-foot siding squares; divide by exact coverage when supplied and round whole pieces upward.

Worked example

A 30 × 10 ft wall with 40 sq ft of openings

The gross area is 300 square feet and the net area is 260 square feet. With 10% waste, the order is 286 square feet, or 2.86 siding squares. A piece count appears only when exact product coverage is entered.

Measurement guidance

Keep product assumptions explicit

  1. Group only equal walls. Calculate unlike sections separately.
  2. Measure gables as triangles. Use base width and vertical gable height.
  3. Deduct openings deliberately. Supplier practices may retain small openings as waste allowance.
  4. Copy usable coverage. Do not substitute nominal panel dimensions for manufacturer coverage.
General-purpose boundary

Materials differ in exposure, overlap, panel size, packaging, fastening, and trim systems. RightQty estimates quantity only and does not approve the selected siding, weather barrier, fastening schedule, or installation.