About ChargeMath
ChargeMath provides free, accurate EV charging calculators powered by real EPA vehicle data and state-specific electricity rates from the EIA. Our goal is to help current and prospective EV owners make informed decisions about charging costs, vehicle comparisons, and home charger investments.
Our Data Sources
- ⚡EPA FuelEconomy.gov — Official fuel economy and EV efficiency ratings for every vehicle sold in the United States.
- ⚡EIA (U.S. Energy Information Administration) — State-by-state residential electricity rates updated regularly from official government data.
Why Trust Our Calculators
- ✓Real government data — Every calculation uses official EPA and EIA figures, not estimates or averages pulled from thin air.
- ✓Transparent methodology — We show you the inputs and formulas so you can verify results yourself.
- ✓No paywalls — Every calculator is 100% free, no account required.
- ✓Regularly updated — Vehicle data and electricity rates are refreshed as new government data becomes available.
Who We Are
Built by a team of EV enthusiasts and data analysts who wanted to make EV ownership math transparent and accessible. We believe the switch to electric should be driven by clear numbers, not marketing hype.
Our Calculators
EV Charging Cost Calculator
Estimate your monthly and annual EV charging costs
Gas vs Electric Calculator
Compare total fuel costs between gas and electric vehicles
Charging Time Calculator
Find out how long it takes to charge any EV
Home Charger ROI Calculator
Calculate the payback period for a Level 2 home charger
Range Calculator
Estimate real-world range under different conditions
EV Tax Credit Calculator
Check federal tax credit eligibility and savings
Electric Bill Impact Calculator
See how EV charging affects your electricity bill