WireSizer Pro - DC cable calc

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.