Exajoules to Zettajoules Converter — EJ to ZJ

Convert Exajoule (EJ) to Zettajoule (ZJ) using the exact conversion factor (1 exajoule = 0.001 zettajoule). See the formula, worked examples, and conversion table.

Exajoules to Zettajoules converter

Converter

Energy Converter

Convert joules, calories, kilowatt-hours, BTU, electronvolts, therms, and mechanical work units.

Result 1 exajoule = 0.001 zettajoule
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From definition

Exajoule is 1000000000000000000 joule units.

To definition

Zettajoule is 1e+21 joule units.

Formula

Result = input x 1e+18 / 1e+21.

Energy uses the joule as the base unit.

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About Converting Exajoules to Zettajoules

Exajoule and Zettajoule both measure energy, and the conversion is especially useful for comparing nutrition labels (kilocalories) against scientific energy figures (joules). Specifically: Exajoule is 1000000000000000000 joule units, and zettajoule is 1e+21 joule units.

Formula

zettajoules = exajoules × 0.001

This factor comes from each unit's defined relationship to the category's base unit: 1 exajoule equals 1e+18 base units, and 1 zettajoule equals 1e+21 base units, so dividing one by the other gives the direct exajoule-to-zettajoule factor of 0.001.

Simple example

1 EJ × 0.001 = 0.001 ZJ

1 exajoule = 0.001 zettajoules.

Real-world example

100 EJ × 0.001 = 0.1 ZJ

100 exajoules = 0.1 zettajoules.

Conversion table

Exajoule (EJ)Zettajoule (ZJ)
1 EJ0.001 ZJ
10 EJ0.01 ZJ
100 EJ0.1 ZJ
500 EJ0.5 ZJ
1,000 EJ1 ZJ
2,000 EJ2 ZJ

Reverse conversion: Zettajoule to Exajoule

0.001 ZJ × 1000 = 1 EJ

0.001 zettajoules = 1 exajoule.

exajoules = zettajoules × 1000

For a page dedicated to this direction, see Zettajoule to Exajoule.

Understanding the Exajoule (EJ)

Exajoule is 1000000000000000000 joule units.

Understanding the Zettajoule (ZJ)

Zettajoule is 1e+21 joule units.

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Frequently asked questions

How many zettajoules are in 1 exajoule?

1 exajoule equals 0.001 zettajoules, using the exact defined conversion factor rather than an estimate.

How do I convert exajoule to zettajoule?

Multiply the exajoule value by 0.001. The converter above does this instantly to whatever precision you set.

How do I convert zettajoule back to exajoule?

Use the reverse factor: 1 zettajoule equals 1,000 exajoules. You can also use the swap control in the converter above to flip the direction instantly.

What is a exajoule?

Exajoule (EJ) is a unit of energy.

What is a zettajoule?

Zettajoule (ZJ) is a unit of energy.

Is the exajoule to zettajoule conversion exact?

Yes. Both exajoule and zettajoule are defined by fixed standards rather than physical artifacts, so the factor of 0.001 used above is exact to as many digits as you choose to display.