About this calculator
Retirement saving is compound growth with a deadline. What matters most is not picking perfect investments — it is how much you have working, how much you add each month, and above all how many years it has to grow. A 35-year-old who saves $500 a month typically ends up with far more than a 50-year-old who saves $1,000, because the earlier money compounds for three extra doublings.
This projection holds your return constant, which real markets never do. Use it to compare choices — retire at 62 or 67, save $400 or $600 — rather than as a promise of an exact balance.
How to use it
- Enter your current age and the age you hope to retire.
- Add everything already saved for retirement (401(k), IRA and other accounts combined).
- Enter your total monthly contribution, including any employer match — the match is part of your saving.
- Set an expected return and compare scenarios: later retirement and higher contributions are the two big levers.
The formula
S is your current savings, C your monthly contribution, r the monthly return (annual return ÷ 12) and n the months until retirement. It is the compound interest formula aimed at a specific age.
Worked example
At 35 with $50,000 saved, adding $500 a month at a 7% return, the projection at 65 is $1,015,810.37. Of that, only $230,000 came out of contributions — the other $785,810.37 is growth. Waiting just five years to start (same saving from 40) drops the result to roughly $700,000.
Frequently asked questions
How much do I need to retire?
A common planning target is 25 times your expected annual spending in retirement (the basis of the 4% rule), adjusted for pensions and Social Security. If you expect to spend $60,000 a year and Social Security covers $24,000, the gap of $36,000 implies a target near $900,000. Your number depends heavily on lifestyle and where you live.
What return should I assume before retirement?
Long-run US stock returns have averaged about 10% a year before inflation, roughly 7% after. Balanced portfolios return less but swing less. Many planners project 5%–7% nominal for a diversified portfolio; being conservative here is safer than being optimistic.
How much should I contribute each month?
A widely used guideline is 12%–15% of gross income including employer contributions, starting in your 20s. Starting later means a higher rate — roughly 20%+ in your 30s and 30%+ in your 40s for the same destination. Capturing the full employer match always comes first: it is an instant 100% return.
Does this include Social Security or inflation?
No. The result is the balance of your own savings, in nominal dollars. To think in today's dollars, lower the return by expected inflation (2–3 points). Social Security is separate income that reduces how much your savings must cover, not part of the balance.