Free calculators

Use these tools in the browser for quick job calculations. Each page includes formulas, examples, screenshots, and an optional iPhone app for field work.

Construction

Rafter Calculator

Common rafter length, plumb cut, and seat cut from span or rise/run.

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Construction

Stair Stringer Calculator

Residential stringer layout from total rise and run.

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Construction

Roof Pitch Calculator

Convert pitch, angle, and slope percent with rafter factors.

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Construction

Concrete Bag Calculator

How many bags of concrete for slabs, footings, and round pours.

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Construction

Concrete Volume Calculator

Cubic feet and yards for slabs, walls, columns, and round forms.

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Construction

Board Foot Calculator

Lumber board feet, linear feet, and volume from dimensions.

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Construction

Feet & Fraction Calculator

Add, subtract, multiply, and divide construction measurements.

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