Mobile-Friendly Electrical Load Calculator: Panel Sizing on Your Phone
Use our mobile-optimized electrical load calculator on any device. Perfect for electricians in the field. Free, NEC 2023 compliant, no app install.
Load Calculations Where You Actually Need Them
📊 NEC 2023 compliant calculations optimized for mobile devices. See our methodology page for methodology.
Electricians do load calculations standing in front of the existing panel, not sitting at a desk. Our calculator is built for one-handed phone use: large touch targets (48px minimum), number-pad input for numeric fields, scrollable appliance list, and instant recalculation as you enter data. No app install, no account, no email. Works offline once loaded.Mobile-Optimized Features
- Touch-friendly inputs: Every input is at least 48px tall—meets WCAG touch target guidelines for gloved hands and shaky ladders
- Number-pad keyboard: Numeric fields trigger the phone's number pad (inputmode="decimal"), not the full keyboard
- Auto-save locally: Your inputs persist in browser storage. Close the page, come back, pick up where you left off.
- Works offline: Load once with an internet connection, continue using without one. The calculator runs entirely in the browser.
- One-thumb navigation: Inputs are stacked vertically—no side-scrolling or pinch-zooming needed.
For Electricians: Faster Than a Spreadsheet
Most electricians use an Excel spreadsheet or a dedicated app for load calculations. Spreadsheets are hard to use on a phone. Dedicated apps cost $10-50. Our mobile calculator is free, runs in any browser, and uses the same NEC methodology. Bookmark it on your phone's home screen—it works like a native app (PWA). Generate a calculation, screenshot it, and attach it to your permit application.
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Frequently Asked Questions
- Does the mobile load calculator work without internet?
- Yes—once the page loads initially, the calculator runs entirely in your browser's JavaScript engine. No server requests are made during calculation. Your inputs are saved to localStorage and persist across sessions.
- Is the mobile calculator as accurate as NEC software?
- For residential calculations using the standard or optional method, yes—the formulas are the same. For complex commercial or industrial calculations with demand factors not covered by NEC 220 Part III, use professional engineering software.