[java] List of Java class file format major version numbers?

I saw this list of major version numbers for Java in another post:

  • 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
  • Java 9 uses major version 53
  • Java 10 uses major version 54
  • Java 11 uses major version 55
  • Java 12 uses major version 56
  • Java 13 uses major version 57
  • Java 14 uses major version 58
  • Java 15 uses major version 59

Where does this list come from? Is there a specific reference for this? Preferably something that shows minor versions too?

This question is related to java version

The answer is


These come from the class version. If you try to load something compiled for java 6 in a java 5 runtime you'll get the error, incompatible class version, got 50, expected 49. Or something like that.

See here in byte offset 7 for more info.

Additional info can also be found here.


I found a list of Java class file versions on the Wikipedia page that describes the class file format:

http://en.wikipedia.org/wiki/Java_class_file#General_layout

Under byte offset 6 & 7, the versions are listed with which Java VM they correspond to.


If you have a class file at build/com/foo/Hello.class, you can check what java version it is compiled at using the command:

javap -v build/com/foo/Hello.class | grep "major"

Example usage:

$ javap -v build/classes/java/main/org/aguibert/liberty/Book.class | grep major
  major version: 57

According to the table in the OP, major version 57 means the class file was compiled to JDK 13 bytecode level


If you're having some problem about "error compiler of class file", it's possible to resolve this by changing the project's JRE to its correspondent through Eclipse.

  1. Build path
  2. Configure build path
  3. Change library to correspondent of table that friend shows last.
  4. Create "jar file" and compile and execute.

I did that and it worked.