BuildMath: Construction Calc

BuildMath is the construction calculator that works the way your tape measure does. Type 12' 6-1/2" exactly as you read it, add, subtract, multiply and divide in feet, inches and fractions, and get answers you can cut to.

Built for carpenters, framers, roofers, contractors, remodelers and serious DIYers.

FEET, INCHES & FRACTIONS
• Enter dimensions with dedicated Feet, Inch and fraction keys
• Answers rounded to the precision you choose, from 1/2" down to 1/64"
• Every result instantly shown in decimal feet, inches, yards and meters
• Mix in metric whenever you need it: m, cm and mm

ROOF FRAMING IN TWO TAPS
Enter any two of pitch, rise and run, and BuildMath solves the rest:
• Common rafter (diagonal) length
• Hip and valley rafter length
• Slope angle and grade
• Jack rafter lengths at your on-center spacing
• Compound miter cuts for crown moulding

STAIRS, SHAPES & LAYOUT
• Stairs: risers, treads and stringer length from total rise
• Arcs, circles and regular polygons
• Studs, blocks, drywall sheets, footings and board feet
• Built-in memory: M+, MR, MC and 9 storage registers

17 STEP-BY-STEP ESTIMATORS
Fill in the fields, read the results. No formulas to remember.
• Concrete slabs and footings: cubic yards and bags, waste included
• Drywall, block walls, flooring and tile
• Wall framing
• Common rafter and hip/valley, basic and advanced
• Stairs, basic and advanced (headroom, opening, throat)
• Circles, columns, cones and arcs
• Crown moulding miter
• Fraction calculator and a full unit converter for length, area, volume and weight

TRIANGLE SOLVER
Enter any three sides or angles and watch the diagram update live. Get area, perimeter, height and every missing side and angle. Switch to right-triangle mode when you only know two values.

BUILD YOUR OWN CALCULATORS
Create custom calculators with your own inputs and formulas for the jobs you do every day.

EVERY ANSWER ON THE TAPE
• Every calculation is saved to a running tape
• Tap any line to reuse that answer
• Save tapes by job, such as "Kitchen Remodel" or "Garage Slab"
• Share a tape as text with your crew or client in one tap

MADE FOR THE JOB SITE
• Big, easy-to-hit keys
• 6 pro themes: Hi-Vis, Graphite, Blueprint, Timber, Architect and Sandstone, with a matching app icon for each
• Match System switches between light and dark automatically
• A tablet layout with the live tape always beside the keypad
• Quick tutorial and a help guide for every key
• No account needed, and all calculations run on your device

Measure twice, calculate once. Download BuildMath and get it right the first cut.

PRIVACY & SUPPORT
• Privacy Policy: https://buildmath.retrytech.site/privacy/
• Terms of Use: https://buildmath.retrytech.site/terms/
• Contact us: help@retrytech.com
Questions, feature ideas or a calculator you'd like to see? Write to us anytime.

Recent changes:
Initial Release