Skip to content
Qalc AI
🇺🇸
EN
English
Watt Hours Calculator
All physics tools
Calculate total energy consumption over time.
Consumption Inputs
Power (Watts)
Time (Hours)
Reset
Total Energy
Watt-Hours
-
Wh
Kilowatt-Hours
-
kWh
Joules
-
J
About this calculator
Quick Reference
1 kWh
3.6 MegaJoules
1000 Wh
1 Unit of electricity
Overview
Watt-hours (Wh) measure energy over time. This tool calculates how much energy a device uses based on its power rating and duration of use.
💡
Pro Tips
1 kWh = 1,000 Wh.
Most electricity bills are charged per kWh.
Multiply Watts by Hours to get Watt-hours.
!
Fun Facts
"A 100W bulb left on for 10 hours uses 1 kWh of energy."
"Electric vehicle batteries are rated in kWh (e.g., 60-100 kWh)."
"Power is the rate of energy use; Energy is the total amount used."
Formula: E = P × t
