The result of your conversion between zeptojoule and gigajoule appears here
To convert between Zeptojoule and Gigajoule you have to do the following:
First divide 1.0e-21 / 1.0e+09 = 0.
Then multiply the amount of Zeptojoule you want to convert to Gigajoule, use the chart below to guide you.
Symbol: zJ
No description
Symbol: GJ
No description