Charging losses and time-of-use pricing

EV Charging Cost Calculator

Estimate a charging session and driving costs, then compare home, workplace and public electricity prices.

Vehicle and charging

Use usable battery capacity and battery-side driving consumption. If your efficiency figure already includes wall/charging losses, set loss to 0 to avoid counting losses twice. The 10% loss default is illustrative, not a vehicle-specific rating.

Home electricity pricing
Workplace electricity pricing
Public electricity pricing

Enter your own rates for all three locations; enter 0 for free charging. Time-of-use share is the percentage of electricity delivered off-peak, not the percentage of hours. Each location is a separate all-charging-at-that-location scenario using the same vehicle and loss assumptions. These scenarios are not added together.

Inputs stay in your browser. No live rate lookup is performed.

How charging cost is calculated

Battery energy added = usable capacity × (target charge - current charge) / 100. Wall energy = battery energy / (1 - loss / 100). For 10% loss, 90% of the electricity drawn reaches the battery; dividing by 0.90 models this loss.

Weighted electricity rate = off-peak rate × off-peak energy share + peak rate × remaining share. Session cost = wall energy × rate. Cost per mile = battery kWh/100 miles / 100 / (1 - loss / 100) × rate.

Monthly cost = unrounded cost per mile × monthly miles; annual cost uses 12 times the monthly miles. Session, monthly and annual totals round independently to cents, so annual cost may differ slightly from 12 times the displayed monthly total. Per-mile cost shows four decimals.

Rates remain constant for the modeled year. Energy-only estimates exclude idle fees, session fees, per-minute charges, subscriptions, taxes not included in your rate, fixed utility charges and charging equipment. This is not a charge-time or battery-range prediction. Actual losses vary with charger, temperature and vehicle.

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