Joule to Watt-hour Conversion Chart
| Joule (J) | Watt-hour (Wh) | Reference Benchmark | Formula Step |
|---|---|---|---|
| 100 J | 0.027778 Wh | Ten-Watt Smartphone Screen Active for Ten Seconds | 100 × 0.0002777778 = 0.027778 Wh |
| 500 J | 0.138889 Wh | Power Consumed by Household Wi-Fi Router in Fifty Seconds | 500 × 0.0002777778 = 0.138889 Wh |
| 1000 J | 0.277778 Wh | One Kilojoule Electrical Equivalent Energy Baseline | 1000 × 0.0002777778 = 0.277778 Wh |
| 1800 J | 0.5 Wh | Half Watt-Hour Standard Micro-Battery Charge Capacity | 1800 × 0.0002777778 = 0.5 Wh |
| 3600 J | 1 Wh | Exact International Definition of One Watt-Hour Energy | 3600 × 0.0002777778 = 1 Wh |
| 7200 J | 2 Wh | Two Watt-Hours Energy Consumed by Modern LED Night Light Overnight | 7200 × 0.0002777778 = 2 Wh |
| 10000 J | 2.777778 Wh | Ten Kilojoules Stored Energy in Compact Flashlight Cell | 10000 × 0.0002777778 = 2.777778 Wh |
| 18000 J | 5 Wh | Energy Consumed by Fast Smartphone Charger in Twenty Minutes | 18000 × 0.0002777778 = 5 Wh |
| 36000 J | 10 Wh | Standard Ten Watt-Hour Smartphone Internal Lithium Battery | 36000 × 0.0002777778 = 10 Wh |
| 50000 J | 13.88889 Wh | Energy Expended by Smart Speaker Streaming for Two Hours | 50000 × 0.0002777778 = 13.88889 Wh |
| 72000 J | 20 Wh | Twenty Watt-Hour High-Capacity Tablet Battery Rating Tier | 72000 × 0.0002777778 = 20 Wh |
| 100000 J | 27.77778 Wh | One Hundred Kilojoules Electric Energy in Power Bank Cell | 100000 × 0.0002777778 = 27.77778 Wh |
| 180000 J | 50 Wh | Fifty Watt-Hour Laptop Computer Battery Pack Standard | 180000 × 0.0002777778 = 50 Wh |
| 360000 J | 100 Wh | FAA Flight Carry-On Maximum Allowed Power Bank Capacity | 360000 × 0.0002777778 = 100 Wh |
| 1000000 J | 277.7778 Wh | One Megajoule Electric Work in Industrial Power Systems | 1000000 × 0.0002777778 = 277.7778 Wh |
Joule to Watt-hour Formula & Unit Definitions
Joule (J)
Source Unit- 3,600 Seconds Multiplier: One watt-hour (Wh) equals exactly 3,600 joules (1 W × 3,600 seconds = 3,600 J). Converting from joules to watt-hours requires dividing by 3,600.
- Battery Capacity Standard: Smartphones, laptops, and drones rate lithium battery capacities in watt-hours (Wh) or milliamp-hours (mAh), which directly convert to joules.
Watt-hour (Wh)
Target Unit- Battery Capacity Standard: Smartphones, laptops, and drones rate lithium battery capacities in watt-hours (Wh) or milliamp-hours (mAh), which directly convert to joules.
- Power and Energy Connection: A device consuming 1 watt of electrical power for 1 hour consumes 1 Wh (3,600 J). For 1 second, it consumes 1 J.
Frequently Asked Questions
Q.How many watt-hours are in one joule?
One joule equals approximately 0.0002777778 watt-hours (1 J = 1 ÷ 3,600 Wh).
Q.What is the reverse conversion from watt-hours to joules?
To convert in reverse, use the Watt-hours to Joules Converter where 1 Wh equals exactly 3,600 J.
Q.Why does 1 Wh equal 3,600 Joules?
Because 1 watt equals 1 joule per second, and there are 3,600 seconds in an hour (1 W × 3,600 s = 3,600 J).
Q.How do you convert battery mAh to Wh and Joules?
Multiply milliamp-hours by nominal voltage and divide by 1,000 to get Wh (e.g. 3,000 mAh × 3.7 V ÷ 1000 = 11.1 Wh = 39,960 J).
Q.How do you convert joules to watt-hours easily?
Divide the number of joules by 3,600.