Comparison

CutOnce vs Flowbox

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

CutOnce

This app provides essential jobsite calculations for contractors and builders, including stair and rafter plans, feet-inch-fraction math, and right triangle solutions. Generate detailed PDF plans offline and export them for shop use or sharing with your crew.

Highlights
  • Stair and rafter PDF plan generation
  • Offline jobsite calculations
  • Feet-inch-fraction math
  • Right angle triangle solver
  • Board feet and concrete estimates
  • Live, zoomable diagrams
Features
Read full description

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.

About

Flowbox

Features
Read full description

Flowbox is a professional toolkit for plumbers — job-site calculators covering drainage, venting, water supply, gas piping, and pipe fitting, all on-device with no account required. PIPE FUNDAMENTALS • Pipe Slope — solve rise, run, or grade against IPC minimums • Pipe Offset — travel and run for 45°, 22.5°, 60°, and other fittings • Flow Rate & Pressure Drop — Hazen-Williams friction loss for water pipe runs • Pipe Volume — water capacity of a pipe segment from ID and length DRAINAGE & VENTING • Drain Sizing — minimum drain pipe size from fixture unit load (DFU) • Vent Sizing — vent pipe diameter from DFU load and developed length • Sump/Ejector Pump Sizing — total dynamic head and horsepower from inflow and lift • Grease Trap Sizing — interceptor capacity from kitchen fixture flow rate SUPPLY & GAS • Water Supply Sizing — distribution pipe size from fixture unit demand (WSFU) • Gas Pipe Sizing — pipe size from BTU load and length, longest-length method • Water Heater Sizing — first hour rating or tankless GPM from peak demand • Water Hammer Arrestor — PDI-WH201 size from branch fixture units • Thermal Expansion — pipe growth and expansion loop size by material WHY FLOWBOX Pro unlock is a one-time purchase — no subscription, ever. No ads. No server required to use any calculator. Free tools (Pipe Slope, Drain Sizing, Pipe Volume) cover everyday use; Pro unlocks the full set. An optional Pro feature lets you sync your saved calculations and projects across your own devices via your own iCloud or Google Drive — off by default, and your data never touches our servers because we don't have any. Flowbox is a reference tool for estimating — always verify pipe slope, drain and vent sizing, water supply sizing, and gas pipe sizing against your local plumbing code (IPC or UPC as adopted locally) and a licensed professional before cutting, sizing, or installing. Gas piping in particular carries real safety consequences if undersized or misrouted.

Screenshots

CutOnce4 screens
Flowbox4 screens

Verdict

The call

The clearest difference is iOS requirement: Flowbox at 13.0 against CutOnce's 17.0. On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. CutOnce sells 1 one-off in-app purchase and Flowbox sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Scorecard1 real difference · 9 level
CutOnce versus Flowbox: the parameters behind the verdict, then further details
ParameterCutOnceFlowbox
PriceFreeFree
Rating5.0 (6 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings6 — better—
Update frequencyEvery 9 days—
AdsNoNo
In-app purchasesYesYes
MonetizationFree—
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.013.0 — better
Further details — not scored
Size14 MB25 MB
Age rating4+4+
DeveloperVerik Labs LLCGABRIELE CHESI

In-app purchases

1 purchases

CutOnce

One-time1
  • Full Access: All Calculators$19.99
1 purchases

Flowbox

One-time1
  • Flowbox Pro Unlock$8.99

Questions

Is CutOnce free?
CutOnce is free to download, with in-app purchases available.
Is Flowbox free?
Flowbox is free to download, with in-app purchases available.
Do CutOnce or Flowbox have ads?
Neither CutOnce nor Flowbox shows ads.

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