How this calculator works
It converts the distance you drive into the electricity your meter records, then multiplies by your tariff:
- Energy into the battery = monthly km ÷ your efficiency (km per kWh).
- Energy from the wall = energy into the battery ÷ 0.9 (about 90% AC charging efficiency).
- Monthly cost = energy from the wall × tariff (₹/kWh); cost per km = monthly cost ÷ monthly km.
Worked example. 1,000 km a month at 6 km/kWh needs about 167 kWh into the battery, roughly 185 kWh from the wall; at ₹8/kWh that is about ₹1,481 a month, or ₹1.48 per km. It is an estimate — slab changes, fixed charges and taxes are not modelled.
Common questions
How do I find my vehicle's efficiency in km per kWh?
Use your vehicle's trip computer or display (often shown as km/kWh, or as Wh/km — divide 1000 by that). A figure from your own driving is more accurate than a brochure number.
Is this my exact electricity bill for charging?
No, it is an estimate. It does not model tariff-slab changes, fixed charges or taxes, and real-world efficiency varies with traffic, load, weather and driving style.
Does this include public or fast charging?
No. It estimates home (AC) charging only. Commercial fast charging is priced separately, often per kWh or per minute at rates unrelated to your home tariff.
What tariff should I use?
The per-unit energy charge (₹ per kWh) from your electricity bill. Reference tariffs on our state guides show their source and verification date; entries marked SAMPLE are demonstration data.
Planning an installation too?
The apartment charger cost calculator adds per-session costs and an installation cost range with visible assumptions.