WireSizer Pro - DC cable calc

Moztcat

In-app purchases

About this app

WireSizer Pro is a professional cable sizing and voltage drop calculator for Android. Size wire and fuses correctly — whether you're wiring a 12V boat, a 240V solar array, or an industrial circuit up to 10,000V.

── ACCURATE CABLE SIZING ──
Enter your system voltage, current, cable run length, and maximum voltage drop — WireSizer Pro instantly calculates the minimum cable cross-section in both mm² and AWG. A recommended size with a 10% safety margin is calculated alongside, so you always have a safe working value and a conservative design value.

── FUSE & BREAKER SIZING ──
Get the correct fuse or circuit breaker size automatically. WireSizer Pro applies the standard 125% rule and rounds up to the nearest standard fuse value from a full table of 21 sizes (5A through 600A). The full calculation breakdown is shown so you understand — and can verify — every result.

── VOLTAGE DROP CALCULATOR ──
See your actual voltage drop in both percentage and volts, cable resistance in mΩ, and power loss in watts. A clear GOOD / WARNING / DANGER safety rating flags any result that exceeds safe operating limits. If your cable needs upsizing to meet ampacity limits, WireSizer Pro flags this automatically.

── MULTI-STANDARD SUPPORT ──
Switch between IEC, NEC, and ABYC wiring standards. Supports copper and aluminium conductors, four installation types (open air, conduit, bundled, submerged) with correct derating factors, and ambient temperature correction from -10°C to 60°C. Works for DC and AC systems from 0.1V to 10,000V.

── PROFESSIONAL TOOLS ──
• mm² to AWG reference table — 20 IEC sizes, searchable, with diameter and ampacity columns
• Fuse sizing guide — 19 load types with minimum, recommended, and maximum fuse ratings
• Installation reference — voltage drop limits, derating factors, ABYC standards, fuse placement rules
• Calculation history — save, rename, reload, and export past calculations
• PDF export — professional report with full methodology, colour-coded results, and disclaimer footer
• Home screen widgets for quick reference

── BUILT FOR PROFESSIONALS AND SERIOUS DIY ──
Electricians, marine engineers, solar installers, RV builders, automotive electricians, and industrial engineers all have different needs. WireSizer Pro covers them all — from a 6V accessory circuit on a classic car to a 480V three-phase industrial feeder.

── HONEST PRICING ──
Free, with banner ads. One optional one-time purchase removes all ads permanently. No subscription. No feature gates. Every calculation is available for free.

What’s new

Improved display on devices running Android 15 and later
Performance and compatibility improvements for newer Android hardware