I get asked this question a lot during my coaching sessions so I thought I'll post a video about it.
In general, I don't go by the way most websites determine how much you'll need to retire, which is based on income. I determine when you are able to retire and how much you'll need based on your current average expenses. For example, if you are spending average $3K a month, which is $36K annually. Let's round that up to $40K. Then we add that yearly plus the 2% or 3% inflation rate and keep doing that till your life expectancy. Then add up the total from the time you plan to retire (ex. age 60 / 65 till maybe you are 80 or 90). See if you can get to that number from now till then. If you need help figuring out if you can retire, I can coach you through this. You don't have to do this alone.