How to Use the EV Home Charging Time & Cost Calculator
When you plug in your EV at home, the two questions that matter most are how long it will take to charge and how much it will add to your electric bill. This calculator takes your battery capacity, current and target charge level, charger power, and electricity rate to estimate both the charging time and the cost.
The calculation factors in charging efficiency loss. The energy actually stored in the battery is not the same as the energy drawn from the wall, since some is lost in the conversion. This calculator assumes about 10% loss so the cost estimate stays closer to what you will actually be billed.
If you're using a Level 2 home charger (3.3-11kW), taking several hours to fully charge is normal. If you need a faster top-up, consider a nearby DC fast charger (50kW or higher) — just remember to update the electricity rate field, since fast-charging rates are usually higher.
Frequently Asked Questions
There is a conversion loss between the energy actually stored in the battery and the energy drawn from the outlet. This calculator assumes about 90% charging efficiency to stay closer to your real electric bill.
A typical home or garage Level 2 charger runs 3.3-11kW, while DC fast chargers run 50kW or higher. Check the actual output of the charger you use for an accurate time estimate.
Check your utility bill or your charging provider's app for the per-kWh rate. If you're on a time-of-use plan with off-peak discounts, use the off-peak rate for a more accurate result.