If you want to retire by age 65, you should be setting aside 10-17 percent of your income. And that's if you start saving as early as age 25.
If you wait until 35 to start, you have to save 15 to 20 percent of your income to retire by 65. Keep in mind that this amount does not include your short-term savings, so it would be on top of any money you're putting in an emergency fund, for example.
That's what researchers at the Stanford Center on Longevity determined in a 2018 report that evaluated how prepared American families are for their golden years by comparing how much they're currently saving to how much they should be saving.