EV Charging Rate Unit Converter

See how quickly a charger adds range and how long it takes to move between state-of-charge breakpoints once you account for efficiency and charging losses.

Nameplate AC or DC charging power available.
Driving efficiency for the conditions you expect.
Usable battery energy from spec sheet or telemetry.
Optional. Leave blank for 10%.
Optional. Leave blank for 80%.
Optional. Leave blank to assume 10% energy loss through cabling and battery heating.

Examples

  • 11 kW charger, 4.0 mi/kWh efficiency, 82 kWh pack, default losses and 10–80% window ⇒ Result: Range gain: 39.6 mi/h | 10–80% time: 5.16 h
  • 150 kW DC charger, 3.2 mi/kWh efficiency, 77 kWh pack, 10% losses, 20–80% window ⇒ Result: Range gain: 432.0 mi/h | 20–80% time: 1.07 h

FAQ

How do I account for different charging curves?

Estimate the average power over the window rather than the peak. For example, a 150 kW charger may average 110 kW between 20% and 80% on many vehicles.

Can I plan a full 0–100% session?

Yes. Set start to 0 and end to 100. Expect the result to be optimistic because most vehicles taper heavily after 80%.

What if my vehicle efficiency varies with climate?

Enter the seasonal efficiency you observe (e.g., 3.0 mi/kWh in winter). The calculator will adjust range gain accordingly.

Additional Information

  • Results show miles per hour of charge and the hours required for the specified state-of-charge interval.
  • Adjust the loss percentage for seasonal temperatures or older battery packs that suffer higher inefficiencies.
  • For tapering DC fast-charge curves, plug in a lower average power than the peak rating for more realistic timing.
  • Convert miles per hour to kilometres per hour by multiplying the reported range gain by 1.609.

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