"How much do I need to retire?" has a surprisingly simple starting answer: 25 times your annual spending. Spend $60,000 a year, target $1,500,000. But the simple answer hides important caveats.

The 4% rule

In the 1990s, financial planner William Bengen studied historical market returns and found that withdrawing 4% of your portfolio in year one, then adjusting for inflation, survived 30-year retirements in nearly all historical scenarios. 4% of $1.5M is $60,000/year. Invert it: annual spending × 25 = target.

It is a planning rule of thumb, not a law of physics. But it converts a vague anxiety ("am I saving enough?") into a concrete number.

Why starting early dominates

Watch what $1,000/month at 7% average returns becomes:

| Years invested | Final value | |---|---| | 10 years | $173,085 | | 20 years | $520,927 | | 30 years | $1,219,971 |

The first 10 years build $173k. The last 10 years add nearly $700k. Compounding is back-loaded — which is why starting at 25 beats saving double starting at 35. Our compound interest calculator makes this visceral: drag the timeline and watch the curve bend.

The caveats that matter

  • 30 years may not be enough. Retiring at 55 means potentially 35–40 years of withdrawals. Many planners now use 3.5% for early retirees.
  • Healthcare is the wild card. The 4% studies assume Medicare-age retirees. Pre-65 health insurance can cost $15,000–$25,000/year for a couple — budget it separately.
  • Spending is not flat. Research shows spending typically declines in later retirement ("the retirement smile"), but long-term care costs can spike at the end.
  • Inflation. 25x in today's dollars is not 25x in 2040 dollars. Your target must grow with prices; investing in assets that outpace inflation is the mechanism.

Build your number

  1. Estimate annual retirement spending (start with current spending minus mortgage/savings, plus healthcare and travel).
  2. Multiply by 25 (or 28–30 for early retirement).
  3. Subtract expected Social Security/pensions (in today's dollars, roughly).
  4. The gap is your savings target — turn it into a monthly number with our retirement savings calculator.

A 30-year-old spending $60k/year needs ~$1.5M. At $1,000/month and 7%, that is about 32 years of steady investing — starting now, not "someday." Also read why starting early beats saving more.

Estimates for planning only, not financial advice. Market returns are not guaranteed; consult a fiduciary advisor for personal planning.