EV Charging Cost Calculator

EV Charging Cost Calculator

Energy needed (battery):45.00 kWh
Energy from grid (with loss):49.50 kWh
Estimated cost:$7.43
Charging time:6.69 h
Assumes constant power; real fast-charging tapers near high SoC.
Charging metricEstimateWhy it matters
Battery energy added45.00 kWhEnergy stored in the vehicle battery.
Grid energy billed49.50 kWhBattery energy plus charging losses.
Session cost$7.43Grid energy multiplied by the price per kWh.
Estimated time6.69 hGrid energy divided by average charger power.

How to read the EV charging estimate

Use the battery capacity and state-of-charge fields to describe the actual charging session, not the full vehicle range. A 20% to 80% session on a 75 kWh battery adds 45 kWh to the battery before losses. The grid energy figure is higher because the wall outlet or public charger must supply the battery energy plus heat and conversion losses.

Home charging is usually cheapest when the price per kWh comes from your electric bill or time-of-use plan. Public fast charging often costs more per kWh, but it can save time on road trips. For a realistic time estimate, enter the average charging power you expect during the session rather than the peak advertised charger speed, because many EVs taper power as the battery gets closer to full.

About This Calculator

Calculate electric vehicle charging costs at home, public stations, and DC fast chargers. Estimate monthly/annual electricity costs based on kWh rate ($0.10-$0.40/kWh), vehicle efficiency (2.5-4.5 mi/kWh), and driving distance (500-2000 miles/month). Compare Level 1 (120V, 3-5 mi/hour), Level 2 (240V, 15-40 mi/hour), and DC Fast (50-350kW, 100-300 mi/30min) charging costs. Analyze home charging ($30-80/month) vs public charging ($60-150/month), peak vs off-peak electricity rates, and EV vs gas savings ($800-1500/year).

Frequently Asked Questions

How do I calculate EV charging cost?

Multiply the battery energy needed by the electricity price, then adjust for charging losses. The calculator does this from battery size, start charge, target charge, and price per kWh.

Why is grid energy higher than battery energy?

Some energy is lost as heat during charging and power conversion. Home Level 2 charging often uses a higher loss assumption than efficient DC fast charging sessions.

Why can real charging time differ from the estimate?

Fast charging power tapers at higher state of charge, and cold batteries, shared chargers, and vehicle limits can reduce the average charging speed.

MT
Mike TorresEngineering & Math Tools Developer

Mike is a software engineer with a background in applied mathematics. He develops and maintains SuperCalc's engineering, conversion, and math utility calculators.

  • M.S. in Applied Mathematics, MIT
  • Former quantitative developer
  • 6 years building computational tools
Published: 2025-06-01github