What is the VinFast Charging Time Calculator?
This tool estimates how long it takes to charge a VinFast electric vehicle — such as the VF 8, VF 9, VF 6, or VF 7 — from its current state of charge (SOC) to a target level. It works for any EV model because you enter the actual battery capacity and charger power yourself. The result is shown in hours and minutes, along with the energy added in kWh.
How to use it
Enter your battery's usable capacity in kWh (for example, ~82 kWh for a VF 8 Eco). Enter the charger power in kW — a typical home AC charger is 7–11 kW, while public DC fast chargers range from 50 to 150+ kW. Set your current charge percentage and the target you want to reach. Finally, set a charging efficiency: AC charging is usually around 85–92%, and DC fast charging often 90–95%. Click calculate to see the estimated time.
The formula explained
Charging time equals the energy you need to add divided by the effective power. The energy needed is the battery capacity multiplied by the percentage gap between target and start SOC. The effective power is the charger's rated power multiplied by the efficiency factor, which accounts for losses as heat in the cables, charger and battery.
$$\text{Time (h)} = \frac{\text{Capacity} \times \dfrac{\text{Target \%} - \text{Start \%}}{100}}{\text{Power} \times \dfrac{\text{Efficiency \%}}{100}}$$
Worked example
Suppose you charge an 82 kWh VinFast battery from 20% to 80% on an 11 kW home charger at 90% efficiency. Energy needed = \(82 \times (80 - 20) / 100 = 49.2\) kWh. Effective power = \(11 \times 0.90 = 9.9\) kW. Time:
$$\text{Time} = \frac{49.2}{9.9} \approx 4.97 \text{ hours}$$
or about 4 hours 58 minutes.
FAQ
Why is real charging slower near 100%? EVs slow charging above ~80% to protect the battery, especially on DC fast chargers, so real times for the last 20% are longer than this linear estimate.
What efficiency should I use? Use ~90% for AC home charging and ~92–95% for DC fast charging as a reasonable default.
Does this work for any EV? Yes — although tuned for VinFast models, you can enter any battery size and charger power for any electric car.
