How it works

The Cheaper Driving calculator compares only one thing: what it costs in fuel and electricity to drive the same number of miles in two different vehicles. This page explains every step so you can check the working.

The formula

For a gas, diesel or hybrid vehicle:

Cost per mile = price per gallon ÷ miles per gallon

For an electric vehicle:

Cost per mile = (1 ÷ miles per kWh) × electricity price per kWh

Multiply either by your annual miles for the yearly cost. The saving is the difference. Weekly figures are the yearly total divided by 52, and monthly figures are divided by 12.

Worked example. A gas pickup rated 20 mpg, with regular gas at $4.47, costs $4.47 ÷ 20 = 22.4¢ a mile. An electric pickup rated 2.03 miles per kWh, with electricity at 18.3¢, costs (1 ÷ 2.03) × 18.3 = 9.0¢ a mile. Over 13,500 miles that is about $3,017 against $1,217 a year, a difference of roughly $1,800 a year, or $150 a month.

Where the vehicle figures come from

All ratings are the combined (city and highway) figures published by the U.S. Environmental Protection Agency and Department of Energy at fueleconomy.gov. That data is public domain. The list covers gas, diesel and hybrid vehicles from model year 2008 to 2027, and electric vehicles from 2010 to 2027.

The EPA reports EV efficiency in kWh per 100 miles, measured from the wall socket, so it already includes charging losses. We convert that to miles per kWh. Plug-in hybrids, natural gas, hydrogen and flex-fuel-only listings are not included, because they either use two energy sources or cannot be compared on a single figure.

Default prices

When you pick a vehicle, the price boxes start from recent U.S. averages: regular gas, premium gas and diesel per gallon from the U.S. Energy Information Administration’s weekly retail fuel prices, and home electricity from the EIA’s residential average. They are only starting points. Your local prices matter more than any national average, so please change them to what you actually pay.

You can also pick your state in the calculator to fill in its average residential electricity price. State averages range widely, from about 13¢ in the cheapest states to more than 30¢ in the most expensive, and the figure is a flat average for the whole state. Many utilities offer time-of-use or EV-specific plans that charge substantially less per kWh for overnight charging, so if you know your own rate, type it in. Those plans can charge more at peak times, so the saving depends on charging off-peak.

What the calculator leaves out

• Public charging. Everything is priced as home charging.
• Incentives. No federal, state or utility credits or rebates.
• Everything except fuel. Insurance, registration, taxes, maintenance, tires, depreciation, financing and the purchase price are not compared.
• Real-world conditions. Ratings come from standard tests. Cold weather, high speeds, heavy loads and towing all change real economy.
• Heavy-duty vehicles. The EPA does not rate vehicles over 8,500 lb gross weight, which excludes most heavy-duty pickups and full-size cargo vans.

The “Not listed” lookup

If your vehicle is not in the list, you can describe it and the site will search the web for a figure using an AI service. It is told to prefer EPA and manufacturer data, and to answer only when it is reasonably sure. The figure it finds is dropped into the box for you to see and change. It is a convenience, not an official rating, so treat it as an indication and check it if the decision matters.

Open the calculator