What This Calculator Does
The VinFast Monthly Fuel Savings Calculator estimates how much money you could save every month by trading your gasoline car for a VinFast electric vehicle (EV). It compares the cost of buying gas for a conventional car against the cost of electricity to charge an EV that drives the same number of miles. Currency is shown in US dollars, but you can use it anywhere by entering your local fuel price and electricity rate in the same currency.
How to Use It
Enter five values: your monthly mileage, your current gas car's fuel economy in miles per gallon (MPG), the price of gas per gallon, the EV's energy consumption in kilowatt-hours per mile (typically 0.25–0.35 kWh/mi), and your electricity rate per kWh. The calculator instantly shows your gas cost, your EV charging cost, the monthly savings, and the projected annual savings.
The Formula Explained
Monthly gas cost equals miles divided by MPG (gallons used) multiplied by the gas price. Monthly EV cost equals miles multiplied by kWh per mile (energy used) multiplied by the electricity rate. Savings is simply the gas cost minus the EV cost:
$$\text{Savings} = \left(\frac{\text{Miles}}{\text{MPG}} \times \text{Gas Price}\right) - \left(\text{Miles} \times \text{kWh/mile} \times \text{Electricity Rate}\right)$$
Worked Example
Suppose you drive 1,000 miles a month in a car that gets 25 MPG, with gas at $3.50/gallon. The gas cost is $$(1000 \div 25) \times 3.50 = 40 \times 3.50 = \$140.$$ A VinFast EV using 0.30 kWh/mile at $0.15/kWh costs $$1000 \times 0.30 \times 0.15 = \$45.$$ Your monthly savings are \(\$140 - \$45 = \$95\), or about $1,140 per year.
FAQ
What consumption value should I use? Most EVs use 0.25 to 0.35 kWh per mile. Check your vehicle's rated efficiency; heavier SUVs and cold-weather driving push it higher.
Does this include charging losses? Charging is not 100% efficient. To be conservative, increase the kWh/mile figure by roughly 10–15%.
Are maintenance or charging fees included? No. This tool only compares fuel versus electricity energy costs. EVs often add further savings from lower maintenance, which this calculator does not estimate.
