A generational garbage collector utilizes a pool-based heap to store objects dynamically generated at runtime. The pool-based heap is configured as a collection of pools where each pool stores objects associated with the same generation. Each pool contains a pool header that identifies the generation of all objects within the pool. The pools are aligned to a memory boundary that is a multiple of the pool size. Select bits of an object's memory address may be used to access the pool header so that an object's generation, which is needed in various phases of the garbage collection process, is readily determined.