EV Load Calc - NEC Compliant

NEC-compliant EV charger load calculator for electricians and contractors. See the exact article, formula, and math behind every result. Works fully offline.

The electrical load calculator built for electricians, contractors, and engineers who install EV charging equipment.

Every calculation references the NEC (NFPA 70) with full transparency — see the exact article, formula, and math behind every result. Built by a low-voltage integrator who got tired of flipping through the code book on ladders. If you spec, permit, or install EV chargers, this is the tool that lives in your pocket.

SINGLE CHARGER SIZING

Size a residential EV charger circuit in seconds. Enter the amperage, voltage, run distance, conductor material, and insulation type. Results include circuit breaker size per NEC 240.6(A) and 210.20(A), minimum conductor gauge per NEC Table 310.16, voltage drop percentage with pass/fail per NEC 210.19(A), automatic wire upsizing when voltage drop exceeds 3%, ambient temperature derating per NEC Table 310.15(B)(1), and a wire cost estimate with custom per-foot override.

MULTI-CHARGER AND FLEET SIZING (PRO)

Size feeder circuits for commercial and fleet installs with 2 to 20 chargers. Compare results with and without an Energy Management System per NEC 625.42 to see how much you save on breaker and conductor sizing.

PANEL CAPACITY CHECK (PRO)

Determine whether an existing residential panel can support an EV charger before you pull a permit. Uses NEC 220 Standard Method with full demand factors and an NEC 220.82 Optional Method toggle for comparison.

CONDUIT FILL CALCULATOR

NEC Chapter 9 conduit fill for EMT, IMC, RMC, PVC, and FMC. Shows fill percentage, pass/fail against Table 1 limits, and recommends minimum conduit size.

SIDE-BY-SIDE COMPARISON

Compare two charger configurations head-to-head. See which option gives you a smaller breaker, lighter wire, or lower voltage drop — differences highlighted clearly.

CHARGER DATABASE

Quick-reference specs for 40+ popular EV chargers from Tesla, ChargePoint, Wallbox, Autel, Siemens, Ford, GM, Rivian, and more.

UNIT CONVERTER

AWG to mm2, feet to meters, watts/volts/amps calculator, and kW to amps with 125% continuous load factor.

SHOW YOUR WORK

Every calculation expands to show step-by-step math with NEC article references. Export results as a formatted PDF or share as text — ready for permit applications, AHJ inspections, or client proposals.

SAVE AND ORGANIZE

Save calculations with custom names and notes. Pull up past jobs instantly.

FULLY OFFLINE

No internet required. No data leaves your device. NEC tables are built into the app for instant results on the job site.

NEC REFERENCES INCLUDED

Article 625 (Electric Vehicle Charging), Article 220 (Branch-Circuit, Feeder, and Service Load Calculations), Article 210 (Branch Circuits), Article 240 (Overcurrent Protection), Table 310.16 (Conductor Ampacities), Table 310.15(B)(1) (Temperature Correction Factors), Chapter 9 (Conduit Fill Tables), Article 220.82 (Optional Method).

DISCLAIMER

EV Load Calc is an educational and reference tool. It is not a substitute for a licensed electrician or your local Authority Having Jurisdiction. Always have a qualified professional review and approve any electrical installation.