Java : how to check the jdk version used to compile a .class file

On Unix/Linux:

javap -verbose MyClass | grep "major"

On Windows:

javap -verbose MyClass | findstr "major"

major version number of the class file format being used

Java 14 uses major version 58
Java 13 uses major version 57
Java 12 uses major version 56
Java 11 uses major version 55
Java 10 uses major version 54
Java 9 uses major version 53
Java 8 uses major version 52
Java 7 uses major version 51
Java 6 uses major version 50
Java 5 uses major version 49
Java 1.3 uses major version 47
Java 1.2 uses major version 46
Java 1.4 uses major version 48

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

https://stackoverflow.com/questions/1096148/how-to-check-the-jdk-version-used-to-compile-a-class-file