How to use the Early Retirement
Retirement planning math involves compounding over decades, which makes early accuracy especially valuable. Small differences in savings rate or return assumption produce dramatically different outcomes at year 30 or 40.
Critical variables to model carefully
- Rate of return assumption: historical S&P 500 averages ~10% nominal, ~7% real (after inflation). Use 6–7% real for conservative planning.
- Contribution rate: even a 1% increase sustained over 20 years can add tens of thousands to the final balance.
- Employer match: always contribute at least to the match ceiling — it's an immediate 50–100% return on those dollars.
- Sequence-of-returns risk: when you retire, a market downturn in the first 5 years is far more damaging than one mid-career. Factor in a glide path to safer assets as you approach retirement.
Run multiple scenarios
Use this calculator to model three cases: a conservative case (5% return, retiring at 67), a base case (7% return, 65), and an optimistic case (9% return, 62). The spread between them reveals how sensitive your plan is to assumptions.
Common gaps in retirement estimates
- Healthcare costs before Medicare eligibility at 65 (often $12,000–$20,000/year out of pocket for early retirees)
- Long-term care costs, which aren't covered by Medicare
- Inflation eroding purchasing power — a $4,000/month budget today is worth $2,200 in today's dollars 20 years from now at 3% inflation
Frequently Asked Questions
How accurate are the results?
The Early Retirement applies a standard formula to your inputs — accuracy depends on how precisely you measure those inputs. For planning and estimation, results are reliable. For high-stakes or professional decisions, cross-check the output with a domain expert or primary source.
What inputs have the biggest effect on the result?
In most financial calculations, the variables with the highest sensitivity are the rate (interest, return, or tax) and time. Try adjusting each by 10-20% to see which one moves the output most — that's where your energy in improving the input estimate is best spent.
How should I interpret the Early Retirement output?
The result is a calculated estimate based on the formula and your inputs. Compare it against the reference values or benchmarks shown on this page to understand whether your result is high, low, or typical. For decisions with real consequences, use the output as one data point alongside direct measurement and professional advice.
When should I use a different approach?
Use this calculator for quick, formula-based estimates. If your situation involves multiple interacting variables, time-varying inputs, or safety-critical decisions, consider a dedicated software tool, professional consultation, or direct measurement. Calculators are most reliable within their stated assumptions — check that your scenario matches those assumptions before relying on the output.