ChargeTruth

What your EV really costs to charge at home and on the road, and how to pay less. Why ChargeTruth?

Now serving San Antonio (CPS Energy). All of Texas is next, then nationwide. Any EV works today; outside San Antonio, enter your electricity price under Fine-tune.

Showing an example: a 2023 F-150 Lightning in San Antonio. Pick your vehicle and ZIP to see your numbers.

Year Make Model ZIP code Miles a day

Charging per year–

Cost per mile–

Full charge–

You save vs gas–

When to plug in

Your rate, hour by hour

What one more kWh costs in each hour of each month, weekdays. Outlined cells are when your EV charges.

Charging

Real-world highway range

See the tests

Source	Speed	Range	Conditions

Plan a trip

Destination Miles one way Trailer Round trip, no charging at the destination

Highway speed

Travel month

Temperature on the road

Leave home at

Stop to charge at

Most drivers stop at 10–20%.

Fast-charge up to

Charging slows sharply past 80%.

Fast-charger speed and price

Average fast-charge speed (kW) Public charger price ($/kWh)Example price. Check your network.

Battery levelCharging stopStop-to-charge level

Stop	Around mile	Arrive	Charge to	Time	Cost

How we calculate this

Energy use starts from the EPA combined rating, which is measured at the wall and includes charging losses. Each month is adjusted for weather: every day in a 10-year temperature record runs through a curve based on fleet studies of real EVs. Energy use is lowest around 65–75°F and rises in cold weather (cabin and battery heating) and in heat (A/C and battery cooling). A heat pump softens the cold penalty.

Highway speed: where we have real-world tests for your vehicle, highway energy use follows the average of those tests at each speed. Otherwise it follows aerodynamic drag, which grows with the square of speed. Towing multiplies energy use for the miles with a trailer attached: about 1.45× for a light trailer, 1.85× for a boat or car hauler and 2.3× for a travel trailer. Gas trucks lose less to speed and towing, and the gas comparison accounts for that.

Home charging is spread over the hours your charger needs, starting at your plug-in time. Cost is the change in your bill from adding that energy on top of your normal home use, so tiered prices apply correctly. The fixed monthly customer charge isn't included because an EV doesn't change it.

Program amounts come from CPS Energy and WeaveGrid announcements, and published figures differ between sources. Confirm current terms before you enroll. This is an estimate, not a bill.