Free EV tool
EV Charging Time & Cost Calculator
Enter your battery, how full it is and where you want it, the charger's power and your tariff. You get charging time and cost including charger losses and the slowdown above 80 % on DC fast chargers.
Charging time
2 h 47 min
at 7.2 kW
Cost
₹160
20 kWh billed
Energy into battery
18 kWh
Charging losses
2 kWh
The vehicle limits this session to 7.2 kW — a bigger charger won't make it faster.
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Charging time & cost report
Charging Time & Cost Calculator ·
Inputs
| Battery | 30 kWh, 20 % → 80 % |
| Charger | 7.4 kW AC (vehicle max 7.2 kW) |
| Tariff | ₹8/kWh |
Results
| Time | 2 h 47 min |
| Cost | ₹160 |
| Energy billed | 20 kWh |
Estimates for planning — verify against datasheets and supplier quotes before you build or invest. Recalculate or share:
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How it's calculated
Charging power is the lower of what the charger supplies and what the vehicle accepts — a 7.4 kW AC charger fills a car with a 3.3 kW on-board charger at only 3.3 kW.
Energy into the battery = battery kWh × (end % − start %). Energy billed is higher because of losses: about 10 % on AC (the vehicle's on-board charger) and 6 % on DC.
Time: on AC, energy ÷ power ÷ efficiency. On DC, charging tapers above 80 % to protect the cells; the calculator uses 40 % of full power for that last stretch, which matches typical published charging curves.
Cost = energy billed × your tariff. Home tariffs in India are usually ₹5–9/kWh; public DC chargers charge about ₹18–25/kWh plus GST.
Results are engineering estimates for planning and learning. Check them against datasheets, supplier quotes and the applicable standards before you build or invest.
Frequently asked questions
How long does a 7.4 kW home charger take?
About 4.5 hours for a 30 kWh battery from 20 % to 80 % (18 kWh ÷ 7.2 kW ÷ 90 % efficiency) — if the car's on-board charger accepts 7.2 kW or more.
Why does fast charging slow down after 80 %?
As cells fill, their voltage rises toward the limit, so the BMS lowers the current to avoid lithium plating and heat. 80 % → 100 % can take as long as 10 % → 80 %.
What do Bharat AC-001 and DC-001 mean?
They were India's early low-power charging standards — 3.3 kW AC sockets and 15 kW low-voltage DC — for small EVs and early fleet cars. New cars use Type 2 AC and CCS2 DC, and light EVs are moving to the LECCS connector.
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