Roofing Calculator
How many shingles do I need?
Enter your home's footprint including the overhangs, and the roof's pitch. We estimate the roof's surface area, the squares and the bundles of shingles.
- Roofing squares
- 16.6 squares (with waste)
- Roof area
- 1,509 sq ft
An estimate to plan and budget with. Measure carefully and check the product’s own figures before you buy.
Results update as you type.
How it’s calculated
- 1
Roof area is the footprint (with overhangs) × a pitch factor: a sloped roof has more surface than the floor beneath it.
- 2
Roofing is sold by the square: 100 sq ft. We add 10 to 15% for cuts, starter rows and ridge caps.
- 3
Standard architectural shingles come 3 bundles to a square.
Before you buy
Count your pitch from inside the attic or from a roofer's measurement; a phone level app can help.
Underlayment, drip edge, flashing and ridge vents are extra materials not counted here.
Check whether the old shingles have to come off: most codes allow at most two layers.
Questions
What is a roofing square?
A square is 100 sq ft of roof surface. Standard architectural shingles are packed about 3 bundles per square.
How do I find my roof's pitch?
Pitch is how many inches the roof rises for every 12 inches across. Measure 12 inches level from the roof surface and then the height up to it, or ask a roofer.