RoofCalc

Roofing calculator

Enter your roof footprint and pitch to get the true roof area, roofing squares, shingle bundles, and installed cost. Free, instant, no signup.

Footprint is the ground area under the roof. The pitch multiplier converts it to true sloped roof area. Includes 10% waste.

Enter your roof footprint and pitch to see squares, bundles, and cost.

Roofing cost by material

3-tab asphalt shingleArchitectural shingleStanding-seam metal

Roofing by house size

1,000 sq ft1,200 sq ft1,500 sq ft1,800 sq ft2,000 sq ft2,500 sq ft3,000 sq ft

Frequently asked questions

How do I calculate roofing squares?

Measure the ground footprint under the roof, multiply by the pitch multiplier (√(rise² + 12²) ÷ 12 — a 6/12 roof is about 1.12) to get the true sloped area, then divide by 100. A 2,000 sq ft footprint at 6/12 is about 22 roofing squares, and roofers order about 10% extra for waste.

How many bundles of shingles are in a square?

Three bundles per square (100 sq ft) for most asphalt and architectural shingles. So a 22-square roof needs about 66 bundles. Metal roofing is sold by the panel instead of by the bundle.

How much does a new roof cost?

Installed roofing runs about $350–$550 per square for 3-tab asphalt, $450–$750 for architectural shingles, and $900–$1,600 for standing-seam metal. A 2,000 sq ft house with a 6/12 architectural roof is roughly $10,000–$16,500.

What is roof pitch and why does it matter?

Pitch is the rise in inches per 12 inches of horizontal run (e.g. 6/12). A steeper pitch means more actual roof surface over the same footprint, so it needs more material — the calculator applies the exact multiplier for your pitch.