CutOnce - Builder's Calculator

Stair and rafter PDF plans, generated offline, on your phone. Feet-inch-fraction math, board feet, deck and concrete estimates: every jobsite calculation in one app. Built for contractors, carpenters, and builders who need accurate answers in the units they actually use.

STAIR CALCULATOR
• Enter total rise and get a complete stair layout
• Unit rise, unit run, number of treads and risers
• Stringer dimensions and layout
• Export a detailed PDF with cut dimensions for the shop

RAFTER CALCULATOR
• Common rafters from span or run
• Ridge height, birdsmouth, and tail cuts
• HAP, overhang, and slope calculations
• PDF export with all the cut angles you need

HIP & VALLEY RAFTERS
• Hip and valley rafter lengths and angles
• Backing angles and cheek cuts
• King common and jack rafter spacing
• Full PDF export for the crew

OFFLINE PDF PLANS
• Shop-ready stair plans with every cut dimension
• Rafter plans with lengths, angles, and layout marks
• Print from the truck or share straight to the crew
• No signal, no cell service, no account required

FEET-INCH-FRACTION MATH
• Enter measurements naturally: 3' 5-3/16" + 2' 10-1/2"
• Add, subtract, multiply, and divide all in fractions
• Choose your precision: 1/2" through 1/64"
• Results displayed in feet-inches-fractions or inches-fractions

RIGHT ANGLE CALCULATOR
• Solve any right triangle from two known sides
• Enter in feet-inches-fractions, get results the same way
• Find the diagonal, rise, or run instantly
• Perfect for squaring walls, checking layouts, and cutting braces

BUILT FOR THE JOBSITE
• Free 7-day trial of every advanced calculator. Basic calculator always free.
• One-time purchase to unlock. No subscriptions. No ads.
• Free updates included
• Works on iPad and iPhone
• English and Spanish language included

Whether you're framing walls, cutting stringers, laying out rafters, or squaring foundations, CutOnce gives you accurate answers in the units you actually use.