Thomas Abeel

We all know that Java is a memory hog. This page aims to give you an idea how much it actually hogs without using a profiler.
Primitive types
A reference to an object is in this listing also considered to be a primitive type.

• boolean: 1 byte
• byte: 1 byte
• char: 2 bytes
• short: 2 bytes
• int: 4 bytes
• long: 8 bytes
• float: 4 bytes
• double: 8 bytes
• reference: 4 bytes

Objects
Each Java object uses the following:

• 8 byte Object overhead