How much memory does a goroutine use

A goroutine starts with a default stack size of 2 KB, which grows and shrinks automatically as needed. This dynamic allocation allows Go to run millions of goroutines efficiently without exhausting system memory. You can inspect the current stack size of a specific goroutine using the runtime.Stack function or by analyzing a heap profile.

Think of a goroutine as a lightweight worker that starts with a tiny workspace (2 KB) instead of a large fixed one. It only grabs more space when it needs to do complex work and gives it back when done. This flexibility lets you run thousands of tasks at once without running out of memory.