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FieldCalc Pro

28 Code-Compliant Trade Calculators

Built for electricians, HVAC technicians, and contractors. NEC 2023, ASHRAE, IRC & ACI references. Works 100% offline.

Try Pro free for 7 days

Three trades. 28 calculators. Every code referenced.

Results you can trust on the job site, offline, with no account required.

Electrical

NEC 2023
  • Ohm's Law Free
  • Voltage Drop Free
  • Wire Sizing Pro
  • Conduit Fill Pro
  • Load Calculator Pro
  • Motor FLA Pro
  • Transformer Sizing Pro
  • Breaker & Fuse Sizing Pro
  • Power Factor Correction Pro

HVAC

ASHRAE
  • BTU Heat Load Free
  • CFM Airflow Free
  • Duct Sizing Pro
  • Equipment Sizing Pro
  • Refrigerant Charge Pro
  • Ventilation Rate Pro
  • Psychrometric Pro
  • Heat Exchanger Pro
  • Cooling Tower Pro

Construction

IRC 2021 / ACI 318-19
  • Concrete Volume Free
  • Paint Coverage Free
  • Lumber Framing Pro
  • Drywall Estimator Pro
  • Roof Pitch & Area Pro
  • Gravel & Aggregate Pro
  • Brick & Block Pro
  • Rebar Spacing Pro
  • Staircase Calculator Pro
  • Tile Estimator Pro

Built for the field, not the office.

Every feature designed for tradespeople who need accurate answers on site, fast.

Code-Compliant

NEC 2023, ASHRAE 62.1, IRC 2021, ACI 318-19. Every calculator cites the applicable standard with edition year.

100% Offline

All calculations run locally on your device. No internet, no account, no data collection. Designed for the job site.

Job-Site Photos New

Attach up to 3 photos per calculation. Document panels, equipment, and site conditions alongside your results.

Batch Calculations New

Compare up to 20 scenarios side-by-side. Run the same calculator across different inputs and export the comparison.

PDF Reports

Generate branded reports with your company logo and license number. Share or print directly from the job site.

CSV Export New

Export project calculations or batch results to spreadsheet-ready CSV files for estimating and documentation.

Imperial & Metric

Toggle between unit systems on any result. All outputs convert automatically with one tap.

Calculation History New

Searchable log of every calculation you've run, filterable by trade and date. Your complete calculation trail.

Simple pricing. Start free.

6 calculators free forever. Upgrade to Pro for the full toolkit.

Free

$0
forever
  • 6 calculators (2 per trade)
  • 1 project
  • Code references
  • Offline access

Monthly

$4.99
per month
7-day free trial
  • All 28 calculators
  • Unlimited projects
  • PDF reports + CSV export
  • Photos, batch calc, history
  • 7-day free trial

Subscriptions auto-renew. Cancel anytime in your Apple ID settings.

Common questions

What is FieldCalc Pro?

A professional trade calculator app with 28 code-compliant calculators for electricians, HVAC technicians, and contractors. References NEC 2023, ASHRAE, IRC 2021, and ACI 318-19.

Does it work without internet?

Yes. Every calculation runs locally on your device. No internet, no account, no data collection. Built for the job site.

Which calculators are free?

6 calculators are free: Ohm's Law, Voltage Drop (Electrical), BTU Heat Load, CFM Airflow (HVAC), Concrete Volume, Paint Coverage (Construction). Pro unlocks all 28.

What code standards are referenced?

NEC 2023 for electrical, ASHRAE 62.1-2022 for HVAC ventilation, ACCA Manual J/S for HVAC loads, IRC 2021 for stairs, and ACI 318-19 for concrete/rebar.

How do I cancel my subscription?

Go to Settings > Apple ID > Subscriptions on your device. You can cancel anytime and retain access until the end of your billing period.