I bought my first electric car about a year ago, and within a week I had a new obsession: how much is this actually costing me? I’d plug in the car, glance at the dashboard, and see some percentage, but I had no gut feel for whether that was $2 or $12. I started doing napkin math: battery is 77 kWh, I’m at 30%, I want to get to 90%, rate is 14 cents per kWh… after about the third time scribbling on an envelope I thought, “I should just make a tool.”
I looked around online. There are EV charging cost calculators, but almost all of them have one of these problems:
I wanted something dead simple: enter your battery size, how full it is right now, where you want it, and your electricity rate. Get a total in dollars. No signups, no “we’ll send you a PDF”, no sparklines.
It’s a single-page calculator that asks for four inputs:
It calculates the kWh you need to add, multiplies by the rate, and shows you the cost. It also accounts for charging losses if you toggle that on (about 10% is realistic for L2 charging). That’s it. No account, no ads, no “this is sponsored by” anything.
Try the EV Charging Cost Calculator →
This isn’t going to be accurate to the penny because your actual charging efficiency depends on temperature, your charger, and your car’s onboard converter. And your utility rate might have time-of-use tiers — if you charge at peak vs off-peak, the cost changes. I included a simple baseline that works for most people (just use your average residential rate). If you have a TOU plan, you might want to use your off-peak rate for nightly charging.
Also: this is a tool I built because I needed it. It’s not trying to get you to switch energy providers, buy a charger, or sign up for a newsletter. It’s literally a form that does the multiplication you could do by hand but faster and less error-prone. That’s the whole point.