Wire Size Calc
NEC Ampacity & Derating
About
Calculate the correct wire gauge for electrical circuits using official NEC ampacity tables and derating factors. Supports various load types, conductor materials, insulation, and installation methods. Works entirely offline for on-site use.
What's New in Wire Size Calc
1.1.0
June 11, 2026
What's new: • AWG / mm² unit toggle in Settings — show wire sizes with their metric cross-section (e.g. 12 AWG · 3.31 mm²) • Metric labels apply everywhere: result card, history and PDF export • NEC sizing math is unchanged — mm² is the exact area of the AWG conductor • Bug fixes and stability improvements Thanks for using ElecTools! Send feedback to support@tradetools.dev.
MoreSubscriptions & In-App Purchases
$2.99
Pro Unlock
No ads, unlimited history, PDF export, dark theme.
Developer apps
FAQ
What is Wire Size Calc?
Wire Size Calc is a mobile application designed to help electricians and engineers determine the correct wire gauge (AWG/kcmil) for electrical circuits based on National Electrical Code (NEC) standards.
How does Wire Size Calc work?
You input parameters like load current, load type, voltage, conductor material, insulation, installation method, and ambient temperature. The app then calculates the recommended wire size with a full derating breakdown.
Does Wire Size Calc require an internet connection?
No, Wire Size Calc works 100% offline. This makes it ideal for use on job sites where internet access may be unreliable.
What NEC versions does Wire Size Calc use?
The application uses official NEC 2023 ampacity tables and derating factors, ensuring compliance with the latest electrical code standards.
What are the 'Pro Features' in Wire Size Calc?
The Pro Features, available via a one-time purchase, include an ad-free experience, the ability to save calculation history, export calculations as PDF reports, and dark theme support.
What devices is Wire Size Calc available on?
Wire Size Calc is available on iPhone, iPad, and iPod devices, as indicated by its supported devices list.
How often is Wire Size Calc updated?
The app was last updated on June 11, 2026, indicating a recent update. The version number is 1.1.0.
Is Wire Size Calc suitable for exam preparation?
Yes, the app is perfect for NEC code exam preparation, including journeyman and master electrician exams, by providing instant wire sizing calculations and derating breakdowns.
