CalculatorCast
Math Finance Health & Fitness Date & Time Unit Converters Computer Physics Chemistry Construction Engineering Statistics Education Everyday Life Biology Automotive Cooking & Food Sports & Fitness Real Estate Photography Electrical Agriculture Travel Business
All Calculators Favorites ()
English Español Français Deutsch Português Italiano Nederlands Polski Türkçe 日本語 한국어 Svenska Norsk Dansk Suomi עברית

Charging Time Calculator

Calculate how long it takes to charge an EV given charger power.

Introduction

Charging Time Calculator — Calculate how long it takes to charge an EV given charger power. Enter Current energy (kWh), Target energy (kWh), Charger power (kW), Efficiency (0-1) to get an instant, accurate result.

Formula

Charging time (hours) = (target kWh − current kWh) / charger power (kW) / charging efficiency.

Step-by-step

  1. Enter the Current energy (kWh).
  2. Enter the Target energy (kWh).
  3. Enter the Charger power (kW).
  4. Enter the Efficiency (0-1).
  5. Click Calculate to see your result instantly.

Real-world example

Example: With Current energy (kWh) = 10, Target energy (kWh) = 60, Charger power (kW) = 7.2, Efficiency (0-1) = 0.9, the Charging Time Calculator gives a result of 7.716.

Frequently Asked Questions

Why is my actual charging time longer than this estimate?
Charging speed typically tapers as the battery fills (especially past ~80% on DC fast charging), which this simple linear formula doesn't model.
Should I use my car's max charge rate or the charger's rated power?
Use whichever is lower — charging speed is capped by the smaller of the two.
What inputs does the Charging Time Calculator need?
You'll need to provide: Current energy (kWh), Target energy (kWh), Charger power (kW), Efficiency (0-1). All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.
How accurate is the Charging Time Calculator?
The Charging Time Calculator applies the formula exactly as calculated — Charging time (hours) = (target kWh − current kWh) / charger power (kW) / charging efficiency. — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.
Is the Charging Time Calculator free to use?
Yes, the Charging Time Calculator is completely free, requires no signup, and runs instantly in your browser.

About the Charging Time Calculator

The Charging Time Calculator uses a real, verifiable formula — Charging time (hours) = (target kWh − current kWh) / charger power (kW) / charging efficiency. — so results are accurate every time, not an approximation.