CutOnce - Builder's Calculator

The construction calculator that generates stair and rafter PDF plans offline, on your phone. No signal, no account, no subscription. Feet and inches fraction math, code-checked stairs, rake wall stud schedules, roofing, masonry, crown angles, footings, deck, drywall, paint, and board feet, with optional material cost on every estimate.

STAIR CALCULATOR
• Enter total rise and get a complete stair layout
• Code check against IRC R311.7 (riser, tread, throat, total rise, headroom), on screen and on the plan, with every limit editable in Settings
• Live, zoomable diagrams: elevation, stringer, detail, and balusters
• Flush (deck) mount stringers, plus a landing split when one flight is too tall
• Export a detailed PDF with cut dimensions for the shop

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

HIP & VALLEY RAFTERS
• Hip and valley lengths, backing angles, and cheek cuts
• King common and jack rafter spacing, with full PDF export

RAKE WALL / GABLE FRAMING
• Every stud length from pitch, run, base height, and on-center spacing
• Top plate bevel and pitch-off-square angles called out
• Dimensioned elevation PDF with the full stud schedule for the saw

ARC & CURVES
• Radius, diameter, arc length, and included angle from a chord and rise
• Or work back from diameter and angle, with a live curve to zoom

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"
• Five memory registers, M1 through M5, for several running totals at once

RIGHT ANGLE & TRIG
• Solve any right triangle from two known sides in feet-inches-fractions
• Sin, cos, and tan with inverses, in degrees or degrees-minutes-seconds
• Perfect for squaring walls, checking layouts, and cutting braces

ROOFING MATERIALS
• Shingle bundles and squares from roof area or measured surface
• Sheathing sheets, underlayment rolls, ridge cap, and lapped drip edge
• Live roof diagram and a shop-ready PDF takeoff

CONCRETE BLOCKS & BRICK (MASONRY)
• Block and brick counts with a fractional course layout
• Mortar yield by product and a CMU width selector (4"–12")
• Optional grout, rebar, bond-beam steel, and wall weight

CROWN MOULDING / COMPOUND MITER
• Saw miter and bevel angles for crown on a compound-miter saw
• Nested (in-position) cutting mode, angle diagram, and a PDF for the saw

MATERIAL TAKEOFFS
• Deck: boards, screws, railing posts, and balusters at code gap
• Drywall: wall and ceiling sheets, 4x8 to 4x14, openings and waste
• Paint: paintable area and gallons by coat, at your can's spread rate
• Board feet: run a whole cut list and total it on the tape
• Concrete: bags or yards with adjustable waste, plus pad and strip footings
• Area, volume, and unit conversion in imperial or metric

COST ESTIMATING
• Total Cost solves any direction: the total, what a budget buys, or the price to hit
• Optional price rows on nearly every material calculator
• Material cost prints right on the tape and the PDF

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.
• Works on iPhone and iPad, in English and Spanish

Framing walls, cutting stringers, laying out rafters, ordering roofing and block: CutOnce gives you accurate answers in the units you actually use.