Fire advocates saving a lot in your 20s and 30s to retire in your 40s
The levels of income you need make this unrealistic for most people
If you are going to do it you need to carefully plan how you will do it
Many people hope to retire ahead of state pension age, maybe in their early 60s or even 50s. But advocates of Financial Independence, Retire Early (Fire) try to retire even earlier, maybe in their 40s, and finance it via extreme saving and investing.
Fire has been attributed to a book published in 1992 called Your Money or Your Life by Vicki Robin and Joe Dominguez. There are a number of US Fire proponents and UK advocates include Maynard Paton, who left nine-to-five work at age 43. He has written about how he did this on his blog at maynardpaton.com/my-story-to-becoming-mortgage-free-and-retiring-early.