Coast FIRE means saving and investing enough early in life that compound growth alone will fund retirement, without needing further contributions.

Once you reach your Coast FIRE number, you can stop aggressive saving and cover only current living costs from work, reducing financial pressure.

The key calculation is estimating how much your current investments will grow by retirement age at a realistic assumed return.

Coast FIRE suits people who want more freedom now, such as lower-paying meaningful work, part-time hours, or a career change, without abandoning retirement security.

It is not a shortcut to early retirement itself, since you still need to work to cover living costs until traditional retirement age in most cases.