# EV Charging Cost Calculator

> Work out what it costs to charge an electric car at your electricity price, including charging losses and session fees, plus the cost per 100 km.

Category: Energy & environment · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/ev-charging-cost-calculator

A charge costs the energy drawn from the grid times the price per kWh, plus any session fee. Grid energy is more than the battery receives because of charging losses.

Also called: Electric car charging cost calculator, Cost to charge calculator.

## Inputs
- Usable battery capacity (unit kWh; default 60)
- Starting charge (unit %; default 20)
- Target charge (unit %; default 80)
- Charging efficiency (unit %; default 90)
- Electricity price per kWh (default 0.30)
- Session or connection fee (default 0; optional)
- Car’s energy use (unit kWh/100 km; default 18)
- Currency

## Results
- Cost of this charge
- Energy bought
- Energy into the battery
- Driving range added
- Cost per 100 km

## Formula

```
Battery kWh = Capacity × (Target% − Start%);  Grid kWh = Battery kWh ÷ Efficiency;  Cost = Grid kWh × Price + Fee;  Range = Battery kWh ÷ Consumption × 100
```

Where:
- Efficiency: share of grid energy stored in the battery
- Consumption: battery energy used per 100 km

## Worked example
1. Battery energy = 60 × 60% = 36 kWh; grid energy = 36 ÷ 0.90 = 40 kWh.
2. Cost = 40 × 0.30 = 12.00.
3. Range added = 36 ÷ 18 × 100 = 200 km, so 12 ÷ 2 = 6.00 per 100 km.

**Result:** Adding 36 kWh to a 60 kWh battery costs 12.00 at 0.30 per kWh, about 6.00 per 100 km.

## What the result means

Compare the cost per 100 km with a petrol car’s fuel cost per 100 km, or with public charging prices, to decide where and when to charge.

## Assumptions and limits
- One price per kWh for the whole session.
- Consumption is battery-side energy, as most trip computers report.
- Public chargers may also bill per minute or for idle time; add those as a session fee.

## Questions

### Why do I pay for more kWh than the battery receives?

Some energy is lost as heat in the charger, cables and battery, so the meter records more than is stored.

### Is off-peak charging worth it?

If your tariff has a cheaper overnight rate, enter it here to see the difference; scheduling charging on a timer is usually free.

## Related calculators
- [EV Charging Time Calculator](https://calculators.geekmidst.com/calculators/ev-charging-duration-calculator)
- [EV vs Petrol Running Cost Calculator](https://calculators.geekmidst.com/calculators/ev-vs-petrol-running-cost-calculator)
- [Fuel Cost Calculator](https://calculators.geekmidst.com/calculators/fuel-cost-calculator)

Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/ev-charging-cost-calculator