A watt-hour is 3,600 joules.
Watt-hours to Ergs Converter — Wh to erg
Convert Watt-hour (Wh) to Erg (erg) using the exact conversion factor (1 watt-hour = 36,000,000,000 erg). See the formula, worked examples, conversion table, and common uses.
Watt-hours to Ergs converter
Converter
Energy Converter
Convert joules, calories, kilowatt-hours, BTU, electronvolts, therms, and mechanical work units.
Context values
Some unit families need one extra value for a physically accurate result.
An erg is a CGS energy unit.
Result = input x 3600 / 1e-7.
Energy uses the joule as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Watt-hours to Ergs
Watt-hour and Erg both measure energy, and the conversion is especially useful for comparing nutrition labels (kilocalories) against scientific energy figures (joules). Watt-hour is most often used for phone, laptop, and power-bank battery capacity ratings.
Formula
ergs = watt-hours × 36000000000
This factor comes from each unit's defined relationship to the category's base unit: 1 watt-hour equals 3600 base units, and 1 erg equals 1e-7 base units, so dividing one by the other gives the direct watt-hour-to-erg factor of 36000000000.
Simple example
1 Wh × 36000000000 = 36,000,000,000 erg
1 watt-hour = 36,000,000,000 ergs.
Real-world example
100 Wh × 36000000000 = 3.6e+12 erg
100 watt-hours = 3.6e+12 ergs.
Conversion table
| Watt-hour (Wh) | Erg (erg) |
|---|---|
| 1 Wh | 36,000,000,000 erg |
| 10 Wh | 360,000,000,000 erg |
| 100 Wh | 3.6e+12 erg |
| 500 Wh | 1.8e+13 erg |
| 1,000 Wh | 3.6e+13 erg |
| 2,000 Wh | 7.2e+13 erg |
Reverse conversion: Erg to Watt-hour
1 erg × 2.777778e-11 = 2.777778e-11 Wh
1 erg = 2.777778e-11 watt-hours.
watt-hours = ergs × 2.777778e-11
For a page dedicated to this direction, see Erg to Watt-hour.
Understanding the Watt-hour
Watt-hour (Wh) measures energy. The energy delivered by one watt of power sustained for one hour — equal to 3,600 joules. It is classified as a metric derived energy unit.
Where it's used: Universal — standard consumer-electronics and battery energy unit worldwide
Wh vs. kWh. The same unit at different scales: 1,000 Wh equals 1 kWh. Wh suits small consumer-electronics batteries; kWh is used for household electricity billing and larger energy storage.
Uses of the Watt-hour today
- Phone, laptop, and power-bank battery capacity ratings
- Electric-vehicle battery capacity specifications
- Small-scale renewable energy (solar panel) output ratings
Understanding the Erg (erg)
An erg is a CGS energy unit.
Watt-hour — sources
- BIPM SI Brochure — Watt-hour as a common energy unit derived from the coherent SI units watt and second (via the hour).
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many ergs are in 1 watt-hour?
1 watt-hour equals 36,000,000,000 ergs, using the exact defined conversion factor rather than an estimate.
How do I convert watt-hour to erg?
Multiply the watt-hour value by 36000000000. The converter above does this instantly to whatever precision you set.
How do I convert erg back to watt-hour?
Use the reverse factor: 1 erg equals 2.777778e-11 watt-hours. You can also use the swap control in the converter above to flip the direction instantly.
What is a watt-hour?
Watt-hour (Wh) measures energy. The energy delivered by one watt of power sustained for one hour — equal to 3,600 joules. It is classified as a metric derived energy unit.
What is a erg?
Erg (erg) is a unit of energy.
Is the watt-hour to erg conversion exact?
Yes. Both watt-hour and erg are defined by fixed standards rather than physical artifacts, so the factor of 36000000000 used above is exact to as many digits as you choose to display.
What is the difference between wh vs. kwh?
The same unit at different scales: 1,000 Wh equals 1 kWh. Wh suits small consumer-electronics batteries; kWh is used for household electricity billing and larger energy storage.
Where is the watt-hour still used today?
Universal — standard consumer-electronics and battery energy unit worldwide