Support

Last updated: June 14, 2026

CalcRig is a mobile calculator app for trade professionals — electrical, HVAC, plumbing, and construction — published by NOTchip. This page is the fastest way to get help, report a problem, or find an answer.

Contact us

Send us a message and we’ll reply within two business days. You can also email support@notchip.com directly.

To help us solve your issue faster, include your device and OS version (for example, iPhone 15 / iOS 18), the CalcRig app version (open the Settings tab and scroll to the bottom), and a description of what happened.

Frequently asked questions

Is CalcRig free?

Yes. Every calculator, in all four trades, is free to use — no account and no credit card required. CalcRig Pro is an optional upgrade that adds unlimited calculation history, PDF reports, project folders, and cloud sync across your devices.

What does CalcRig Pro cost?

Pro is available as a monthly, yearly, or one-time Lifetime purchase. The exact price for your region is shown in the app before you buy. The Lifetime option is a single payment and never renews.

Do the calculators work offline?

Yes. Every calculation runs on your device, so CalcRig works with no signal — in a basement, a mechanical room, or anywhere on site. An internet connection is only needed for account sign-in and optional cloud sync.

Do I need an account to use it?

No. You can use every calculator without signing in. An account is only needed to save projects, sync across devices, and manage a subscription. You can sign in with Apple, Google, or email.

Which codes and standards does CalcRig reference?

Each result shows the standard behind it — including the NEC (such as 310.16 ampacity and Chapter 9 conduit fill) for electrical, ASHRAE and ACCA Manual J methodology for HVAC, and UPC/IPC fixture-unit tables for plumbing. Always confirm against the code edition adopted by your local jurisdiction.

How do I export a PDF report?

PDF export is a Pro feature. After running a calculation, tap Share and choose PDF to generate a report with the inputs, result, formula, and code reference. Free accounts can share results as plain text.

How do I restore a purchase?

Open the Settings tab and tap Restore Purchases. Make sure you are signed in to the same App Store or Google Play account you used to buy Pro.

How do I cancel my subscription?

Subscriptions are billed and managed by Apple or Google, not by CalcRig. On iOS: Settings → your name → Subscriptions. On Android: Play Store → profile → Payments & subscriptions. Cancelling stops future renewals; Pro stays active until the end of the period you paid for. A Lifetime purchase never renews, so there is nothing to cancel.

Does my data sync across devices?

Cloud sync is a Pro feature. Sign in with the same account on each device and your calculation history, projects, and preferences sync automatically. Without Pro, your data stays on the device it was created on.

How do I delete my account or data?

See Delete your account for step-by-step instructions to remove your account and server-side data, or email support@notchip.com.

Codes and accuracy

CalcRig’s calculations are tools to assist qualified trade professionals and are provided as estimates. They do not replace engineered design, manufacturer specifications, or the judgment of a licensed professional. Always verify results against the codes and standards adopted by your local authority having jurisdiction (AHJ) before relying on them.

Account, privacy, and terms

• Delete your account — remove your account and data.
• Privacy Policy — what we collect and how we use it.
• Terms of Service — the terms that govern your use of CalcRig.

For any question this page doesn’t answer, email support@notchip.com.