Electrical, plumbing, HVAC, welding, masonry, carpentry, estimating & conversions — all code-compliant, all offline, all in your pocket.
Free 7-day trial · $14.99 per trade or $29.99 for all trades
Grouped by workflow, not alphabetically. Wire & conduit first, then service & load, then motors. The way your day goes.
Every calculation references the actual code book tables — not approximations. The same tables your inspector uses.
Table 9 impedance values with AC skin effect correction for 2/0+ conductors. Table 310.16 ampacity. Chapter 9 conduit fill percentages.
DFU tables, fixture unit calculations, gas pipe sizing per IFGC. Drainage slope and water supply demand curves.
R311.7.2 headroom clearance for stairs. Joist span tables. Rafter sizing. Floor opening calculations for code-compliant stairways.
NEC Table 9 impedance values — not the simplified DC resistance most apps use. Includes AC skin effect correction for conductors 2/0 AWG and larger, power factor input, and automatic pass/fail against NEC 210.19(A) and 215.2(A) thresholds.
Input total rise, and the calculator outputs riser height, tread depth, number of treads, total run, stringer length, and the floor opening dimension for IRC R311.7.2 headroom clearance. No more guessing if your header is far enough back.
10 welding calculators including AWS D1.1 preheat requirements, carbon equivalent (CE & Pcm), heat input, filler metal selection, and gas flow rates. Builder's Helper doesn't have it. Construction Master doesn't either. Nobody does.
Every calculation generates a clean, branded PDF with your inputs, the step-by-step work, and the code reference. Share it with your foreman, email it to the inspector, or save it to your project folder. Professional documentation from the field.
No subscriptions. No recurring charges. Not $36/year like Construction Master.
| Feature | Contractor's Cheatsheet | Construction Master | Builder's Helper MAX |
|---|---|---|---|
| Total calculators | 89 | ~12 | ~16 |
| Trades covered | 8 | GC only | Carpentry/GC |
| Electrical (NEC) | 15 calculators | ✗ | ✗ |
| Plumbing (IPC) | 13 calculators | ✗ | ✗ |
| Welding (AWS D1.1) | 10 calculators | ✗ | ✗ |
| HVAC | 8 calculators | ✗ | ✗ |
| Code compliance tables | NEC · IPC · IRC | None | None |
| PDF reports | ✓ | ✗ | ✓ |
| Pricing | $29.99 once | $20–36/yr | ~$6 once |
| Subscriptions | None | Annual | None |
Yes. Every calculator works without an internet connection. All code tables are built into the app. Use it in a basement, on a roof, in a tunnel — anywhere you have your phone.
The app defaults to NEC 2023 and includes a toggle for 2020 where table values differ. Impedance values, ampacity tables, and conduit fill percentages are pulled directly from the code book.
Yes. Every calculation generates a branded PDF showing your inputs, step-by-step work, and code references. Share via AirDrop, text, email, or save to your files.
Unlock just the trade you need for $14.99. Electricians get all 15 electrical calculators. Plumbers get all 13 plumbing calculators. You can always upgrade to all trades later — we'll credit your first purchase.
iOS first, Android on the roadmap. If you want to be notified when it ships, drop your email below.
Construction Master is a feet-inch-fraction calculator with basic dimensional math. It has zero trade-specific calculators, no code compliance, no NEC tables, no pipe sizing, no welding — and charges $20–36/year. This app has 89 calculators across 8 trades for one payment.
Free for 7 days. Every calculator. Every trade.
Download on the App Store