EV charging cost calculator
Battery size and state of charge give the units; your tariff gives the rupees. See the session cost, cost per km and the monthly bill.
| Breakdown | Value |
|---|
Estimate. The method and sources are on this page — check them against your own case before you act.
How it is calculated
A charging session is metered in units, the same unit on your electricity bill. The calculation is battery capacity × state-of-charge change, adjusted for losses, then multiplied by the tariff.
Energy added = battery × (target − start) ÷ 100 · Grid units = energy added ÷ (1 − losses) · Cost = units × tariff
Work out the energy added
A 40 kWh battery charged from 20% to 100% takes on 32 kWh. That is the energy that actually enters the battery, not the energy the meter sees.
Add charging losses
Heat in the charger, cable and battery means the meter supplies more than the battery stores. At 10% losses, 32 kWh in the battery draws about 35.6 kWh from the grid.
Multiply by your tariff
Home tariffs are per slab and vary by state; public chargers have their own rate. At ₹9 per unit, the 35.6 units cost about ₹320. The same maths gives the cost per km and per month.
Charging cost reference
| Item | Typical value | Notes |
|---|---|---|
| Home AC charging | ₹6–12 per kWh | Depends on state slab and fixed charges |
| Public AC charging | ₹10–18 per kWh | App-based, often with a parking fee |
| Public DC fast charging | ₹15–25 per kWh | The most expensive way to charge |
| Charging losses | 5–15% | Lower for AC home charging in mild weather |
| EV efficiency | 5–8 km/kWh | Small cars higher, large SUVs lower |
| Battery sizes | 25–60 kWh | Most mainstream EVs in India in 2026 |
| 1 unit | 1 kWh | The same unit as your electricity bill |
What most pages get wrong
Your car is billed in the same unit as your fridge
One kWh is one unit. A 40 kWh EV charged from zero draws about 44 units at the meter once losses are added.
Where you charge matters more than what you drive
Home charging at ₹9 per unit and public DC charging at ₹20 per unit are more than twice apart. The same car costs very different amounts per km depending on the plug.
Charging to 80% is cheaper and kinder to the battery
The last 20% charges slowly and uses more energy in thermal management. For daily use, charge to 80% and save the full charge for long trips.
Efficiency is the number to watch
Cost per km is tariff divided by efficiency, adjusted for losses. Dropping from 7 km/kWh to 5 km/kWh raises the per-km cost by 40% — which is why the efficiency input matters more than the battery size.
Frequently asked questions
How much does it cost to fully charge an EV at home?+
How much does an EV cost per km?+
What are charging losses and should I include them?+
Is it cheaper to charge at home or at a public charger?+
How long does a full charge take?+
Does battery size change the cost per km?+
Sources, dates and a changelog.
Every number this calculator uses is either an input you control or a value from the sources below. The formula is compiled and tested at build time, so the page cannot ship with a broken calculation.
Sources
- MERC — Maharashtra Electricity Regulatory Commission tariff orders
- BEE — Bureau of Energy Efficiency (1 unit = 1 kWh)
- Checked by hand, not scraped
This page
- Last verified: 29 October 2026
- Next review: 29 April 2027
- Vertical: Vehicle & Transport
- Build tests: 4 passed
- Changelog: 1 entry
How we handle errors
- Spotted a mistake? Report it — we correct and log it.
- Corrections appear in the changelog below.
- Read the methodology and the disclaimer.