Retiring at 60 is achievable for many people — it requires 25–28× annual expenses and a savings rate of 20–30% over a working career. Here's how to calculate your exact number.
If you plan to live past 90 or want more margin, use 3.5% (28× expenses). Most financial planners consider 4% appropriate for a 60-year-old with a 30-year expected retirement.
At 60, you're typically within 5–10 years of state pension eligibility. Factor this in: if state pension will cover $12,000/year from age 67, you only need your portfolio to cover the remaining expenses — significantly reducing your required savings.