Wire Size & Ampacity Calc

The right conductor, code-checked: ampacity with real derating, breaker suggestion and conduit fill — NEC and IEC side by side.

Size conductors the way the code book does — without flipping pages.

Pick NEC or IEC, enter the load, set the real conditions, and read the minimum conductor size on one screen.

WHAT IT DOES

• NEC (NFPA 70) Table 310.16 ampacities: copper and aluminum, 60/75/90 °C columns, 14 AWG to 500 kcmil
• IEC 60364-5-52 method C ampacities: copper, PVC or XLPE, 1.5 to 300 mm²
• Ambient-temperature correction and grouping adjustment applied automatically
• 125 % continuous-load design current
• Suggested breaker from the standard ladder, small-conductor caps included
• Pro: full derating breakdown, conduit-fill summary (NEC Ch. 9 Table 1), voltage-drop cross-check, history and one-page PDF export

BUILT FOR THE FIELD Big glove-friendly keys, an Outdoor Bright theme for direct sunlight, and everything works offline.

PRIVACY Everything stays on your phone. No account, no ads, no tracking.

A planning aid, not a substitute for the code — always confirm results with your local code authority and the current edition.

PRO UNLOCKS: both NEC and IEC standards, full derating detail, conduit fill, voltage-drop checks, history and PDF export. Available as an auto-renewable subscription (monthly or yearly) or a one-time Lifetime purchase.

——— Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://hdappstudio.com/wiresize/privacy/