What this calculator does
The VinFast VF3 Charging Cost Calculator estimates how much electricity you will pay to charge your VinFast VF3 mini electric SUV from one battery level to another. It accounts for the car's usable battery capacity, real-world charging losses, and your local electricity price, so the figure reflects what actually shows up on your bill rather than the idealized energy stored in the pack.
How to use it
Enter your VF3 battery capacity in kWh (around 18.64 kWh by default), the charging efficiency (typically 85–92% for AC home charging), your starting and target state of charge as percentages, and your electricity rate per kWh in your local currency. The calculator returns the total session cost plus the energy delivered to the battery and the energy drawn from the grid.
The formula explained
First the state-of-charge gain is found: (Target − Start). Multiplying by capacity and dividing by 100 gives the energy stored in the battery. Because chargers lose some energy as heat, that figure is divided by efficiency to get the energy pulled from the grid. Finally, multiply by your rate to get cost:
$$\text{Cost} = \frac{\text{Capacity} \times \dfrac{\text{Target} - \text{Start}}{100}}{\dfrac{\text{Efficiency}}{100}} \times \text{Rate}$$
Worked example
Charging an 18.64 kWh VF3 from 20% to 100% at 90% efficiency with a rate of 0.17 per kWh: the gain is 80%, so \(18.64 \times 0.80 = 14.912\) kWh into the battery. Divided by 0.90 gives about 16.569 kWh from the grid. At 0.17 that is roughly 2.82 per charge.
FAQ
Why include charging efficiency? AC chargers waste 8–15% of energy as heat and conversion loss, so the grid draws more than what reaches the battery. Ignoring it underestimates cost.
What battery size should I use? The VF3 uses an LFP pack of roughly 18.64 kWh; use your model's spec if it differs by market.
Does this work for any currency? Yes. Enter the rate in whatever currency your utility bills you and the result is in that same currency.
