Terajoule is 1000000000000 joule units.
Terajoules to Watt-hours Converter — TJ to Wh
Convert Terajoule (TJ) to Watt-hour (Wh) using the exact conversion factor (1 terajoule = 277,777,777.8 watt-hour). See the formula, worked examples, conversion table, and common uses.
Terajoules to Watt-hours 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.
A watt-hour is 3,600 joules.
Result = input x 1e+12 / 3600.
Energy uses the joule as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Terajoules to Watt-hours
Terajoule and Watt-hour both measure energy, and the conversion is especially useful for comparing nutrition labels (kilocalories) against scientific energy figures (joules). Specifically: Terajoule is 1000000000000 joule units, and a watt-hour is 3,600 joules.
Formula
watt-hours = terajoules × 277777777.778
This factor comes from each unit's defined relationship to the category's base unit: 1 terajoule equals 1e+12 base units, and 1 watt-hour equals 3600 base units, so dividing one by the other gives the direct terajoule-to-watt-hour factor of 277777777.778.
Simple example
1 TJ × 277777777.8 = 277,777,777.8 Wh
1 terajoule = 277,777,777.8 watt-hours.
Real-world example
100 TJ × 277777777.8 = 27,777,777,780 Wh
100 terajoules = 27,777,777,780 watt-hours.
Conversion table
| Terajoule (TJ) | Watt-hour (Wh) |
|---|---|
| 1 TJ | 277,777,777.8 Wh |
| 10 TJ | 2,777,777,778 Wh |
| 100 TJ | 27,777,777,780 Wh |
| 500 TJ | 138,888,888,900 Wh |
| 1,000 TJ | 277,777,777,800 Wh |
| 2,000 TJ | 555,555,555,600 Wh |
Reverse conversion: Watt-hour to Terajoule
1 Wh × 3.6e-9 = 3.6e-9 TJ
1 watt-hour = 3.6e-9 terajoules.
terajoules = watt-hours × 3.6e-9
For a page dedicated to this direction, see Watt-hour to Terajoule.
Understanding the Terajoule (TJ)
Terajoule is 1000000000000 joule units.
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
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 watt-hours are in 1 terajoule?
1 terajoule equals 277,777,777.8 watt-hours, using the exact defined conversion factor rather than an estimate.
How do I convert terajoule to watt-hour?
Multiply the terajoule value by 277777777.8. The converter above does this instantly to whatever precision you set.
How do I convert watt-hour back to terajoule?
Use the reverse factor: 1 watt-hour equals 3.6e-9 terajoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a terajoule?
Terajoule (TJ) is a unit of energy.
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.
Is the terajoule to watt-hour conversion exact?
Yes. Both terajoule and watt-hour are defined by fixed standards rather than physical artifacts, so the factor of 277777777.8 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.