To find the Java Version of the Compiled class file.

On Unix/Linux:

javap -verbose MyClass | grep "major"

On Windows:

javap -verbose MyClass | findstr "major"


  • Java 1.2 uses major version 46
  • Java 1.3 uses major version 47
  • Java 1.4 uses major version 48
  • Java 5 uses major version 49
  • Java 6 uses major version 50
  • Java 7 uses major version 51
  • Java 8 uses major version 52

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