WireCalc Support

Questions, bug reports, feature requests, or a calculation that looks wrong — all of it goes to the same place:

WireCalc is a reference calculator — if a result looks off, we want to know. The fastest fix comes from an email that includes:

• the exact inputs you entered and the screen you were on
• what the app showed vs. what you expected
• your device and iOS version (Settings → General → About)

If a table-driven value (ampacity, voltage drop, fill) looks wrong, tell us the exact inputs and which NEC table you're checking against — table values do get revised between code editions, and we track that.

How do I use the guided calculators?

Follow the numbered input sections, then tap Review live result. Wire Size lets you expand Why this size? Show calculation. Use Save calculation for local history, Copy result for the clipboard, or Share for a summary sent to a destination you choose.

Can I use Celsius?

Temperatures default to Fahrenheit. Open More > Settings > Temperature units to choose Celsius. Changing units preserves the entered conditions.

How are grounding conductors counted for box fill?

The current calculation uses one volume allowance for one through four entering grounding conductors, then one-quarter allowance for each additional conductor, based on the largest entering grounding conductor. Pigtails staying entirely inside are not entered in that count. Verify installation-specific conditions against the adopted code.

Do I need to sign in or create an account?

No. WireCalc has no account, login, or cloud sync — open it and it works.

I uninstalled the app and lost my calculation history — can I get it back?

Truck and Toolbox does not keep a cloud copy of your history. Deleting the app removes local app data, but an iCloud or computer backup may be able to restore it. Previously shared summaries can also remain with their recipients. Availability depends on your backups and device settings; recovery is not guaranteed. See our Privacy Policy.

Are the NEC tables official or current?

WireCalc uses reference tables based on NEC 2023 and standard formulas to the values you enter, but it is not a substitute for the current adopted code or a licensed electrician's judgement. NEC is a registered trademark of the National Fire Protection Association; WireCalc is not affiliated with or endorsed by the NFPA.

Do you offer refunds?

Refunds for App Store purchases go through Apple, not us directly — request one at reportaproblem.apple.com. Email us too if something didn't work as expected; we'd like to know either way.

Can you add [feature]?

Maybe — email us. We read every request even if we can't promise a timeline.

Calculations run on-device without automatic data collection. Copying, sharing, support email, external links, and device backups are explained in the Privacy Policy.