EV Charging Cost Calculator
Calculate the cost to charge your EV's battery, accounting for charging efficiency losses.
- Free to use
- Accurate results
- No registration required
- Works on all devices
Enter your battery capacity, electricity rate, and charge levels to calculate the true cost of charging, including efficiency losses.
₹
%
AC home charging is typically 85-90% efficient; DC fast charging is often slightly higher.%
%
Your result
₹284.44
Total charging cost
Energy added to battery32 kWh
Energy drawn from the grid35.56 kWh
AI explanation
Formula
Energy drawn from grid = energy added to battery ÷ charging efficiency; cost = energy drawn × electricity rateWorked example
40 kWh battery, 20% → 100%, 90% efficiency
| Field | Value |
|---|---|
| Battery capacity (kWh) | 40 |
| Electricity rate (per kWh) | 8 |
| Charging efficiency | 90 |
| Current charge level | 20 |
| Target charge level | 100 |
| Total charging cost | 284.44 |
| Energy added to battery | 32 |
| Energy drawn from the grid | 35.56 |
Assumptions
- Charging isn't 100% efficient — some energy is lost as heat during AC-to-DC conversion, so you're billed for more energy than actually ends up in the battery.
- Uses your entered electricity rate for the entire session — actual home tariffs may have slab-based or time-of-day pricing not modeled here.
Frequently asked questions
Why am I billed for more energy than my battery capacity?
Charging efficiency losses — energy is lost as heat while converting AC grid power to DC for the battery. A 90% efficient charge means you draw about 11% more energy from the grid than actually gets stored.
Does charging speed (AC vs DC fast charging) affect efficiency?
Generally yes — efficiency varies by charger type and can also drop somewhat at very high charge levels (above ~80%) as the battery management system tapers charging speed.
Should I always charge to 100%?
Many EV manufacturers recommend routine charging to 80-90% for daily use, reserving 100% charges for longer trips, to help preserve long-term battery health — check your vehicle's specific guidance.