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Free Construction Calculators for Pros & DIYers
Stair layout, rafter lengths, concrete yardage, miter angles, and more. Built for contractors, tradespeople, and serious DIYers.
Exact Math
Fractional arithmetic with no rounding errors. Construction-grade precision.
Jobsite Ready
48px touch targets, oversized inputs, and mobile-first design for work gloves.
Code Compliant
IRC and IBC building code checks built into stair, railing, and rafter calculators.
Instant Results
All calculations run client-side. No server round-trip, no waiting. Just answers.
Construction Calculators
24 professional calculators ready to use, with 0 more in development.
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Stair Calculator
Calculate stair rise, run, stringer length, riser height, and tread depth. IRC/IBC code compliance checks with interactive SVG diagrams and PDF export.
Rafter Calculator
Calculate common, hip, valley, and jack rafter lengths with plumb cuts, level cuts, and birdsmouth dimensions. Miter saw and protractor angle modes.
Compound Miter Calculator
Calculate miter and bevel angles for simple and compound cuts. Dual output modes for miter saw settings and protractor marking. Crown molding presets included.
Feet & Inches Calculator
Add, subtract, multiply, and divide measurements in feet, inches, and fractions. Running tape, memory registers, and simultaneous imperial/metric output.
Concrete Calculator
Calculate concrete volume in cubic yards for slabs, footings, columns, and steps. Bag count for 60/80/90 lb bags. Multi-section calculator with rebar spacing.
Roof Pitch Calculator
Convert between roof pitch (x/12), degrees, percent grade, rise, run, diagonal, and slope ratio. Enter any two values to calculate all seven.
Board Foot Calculator
Calculate board feet from nominal lumber dimensions. Species database with Janka hardness and pricing. Lumber list builder with waste factor.
Baluster Calculator
Calculate baluster spacing for decks, railings, and stairs. Three modes: limited opening, evenly spaced, and on-center. 4-inch code compliance check.
Drywall Calculator
Calculate drywall sheets needed for walls and ceilings. Room mode for quick estimation. Joint compound, tape, and screw count included.
Masonry Calculator
Calculate the number of bricks, blocks, tiles, or pavers needed. Custom unit sizes with mortar joint estimation.
Fence Calculator
Calculate fence posts, rails, pickets, and panels for any fence length. Multiple spacing and rail configurations.
Deck Board Calculator
Calculate deck boards, joists, joist hangers, and fasteners. Support for perpendicular, diagonal, and herringbone layouts.
Roofing Calculator
Calculate shingle bundles, sheathing sheets, ridge cap, and underlayment for any roof. Pitch-adjusted area calculation.
Framing Calculator
Calculate studs, plates, and headers for wall framing. Support for 16" and 24" on-center spacing with door/window openings.
Paint Calculator
Calculate gallons of paint and primer needed for any room. Subtract doors and windows. Multiple coats and trim paint estimation.
Rake Wall Calculator
Calculate individual stud lengths for rake (gable) walls. On-center spacing with complete cut list.
Arc Calculator
Calculate arc dimensions from any two inputs: radius, chord, height, angle, or arc length. Stud layout for curved walls.
Polygon Calculator
Calculate polygon angles, miter settings, side lengths, and area. Perfect for gazebos, decks, and custom woodworking.
Siding Calculator
Calculate siding panels and sheet material for walls including gable areas. Pitch-adjusted gable calculation.
Unit Conversion Hub
Convert between all construction-relevant units: length, area, volume, weight, and angles. Fractional precision from 1/2" to 1/64".
Volume Calculator
Calculate volume and area for cylinders, cones, gables, triangles, slabs, polygons, and arc segments.
Gravel Calculator
Calculate gravel, sand, topsoil, and crushed stone volume in cubic yards and tons. Truckload and cost estimation.
Square-Up Calculator
Calculate the diagonal measurement to square any rectangle. Foundation, deck, and wall squaring with 3-4-5 reference.
Electrical Load Calculator
Calculate total electrical load, recommended panel size, and wire gauge requirements per circuit.
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Browse by Category
Framing Calculators
Advanced layout calculators for stair, rafter, rake wall, and miter angle framing.
Roofing Calculators
Roof pitch, rafter length, shingle estimation, and roofing material calculators.
Concrete & Volume Calculators
Concrete yardage, bag count, footing, gravel fill, and general volume calculators.
Material Estimation Calculators
Drywall, masonry, fence, deck board, paint, and siding material calculators.
Conversion & General Math Tools
Feet-inches-fractions calculator, unit conversions, board foot calculator, and more.
Pro-Grade Calculators, Zero Cost
Construction Bros puts stair layout, rafter math, concrete estimates, and more right in your browser — no app to download, no subscription, no signup.
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