Retirement Calculator
Free retirement calculator. Estimate your nest egg at retirement age from current savings, monthly contributions, expected return, and years until retirement.
Quick answer
Future value = (current savings × (1+r)^n) + monthly contribution × ((1+r)^n − 1) ÷ r, where r is the monthly return and n is months until retirement. The 4% rule says you can withdraw 4% of your nest egg per year in retirement with low risk of running out over 30 years.
Retirement Savings Calculator
How it works
Projects your retirement savings balance based on your current age, retirement age, current balance, monthly contributions, and expected annual return. Uses standard compound-interest math with monthly contributions.
When to use it
Use this to sanity-check whether you're on track for retirement, or to see how a contribution increase changes your trajectory. The 4% rule says you need roughly 25× your annual expenses saved to retire safely.
Common mistakes
Assuming 10% returns based on historical stock-market averages. Real returns (after inflation) are closer to 6–7%, which makes a meaningful difference over 30 years. Also: forgetting to factor in Social Security, which covers a chunk for most retirees.
How the retirement calculator works
This is a future-value calculation with two compounding components: the lump sum you already
have invested, and the stream of monthly contributions you will make between now and retirement.
The lump sum grows as FV = PV × (1 + r)^n, where PV is your current balance, r is
the monthly rate of return (annual rate ÷ 12), and n is months until retirement. The contribution
stream uses the future-value-of-annuity formula:
FV = PMT × ((1 + r)^n − 1) ÷ r, summed across every month between now and retirement.
The default 7% return is the long-run real (inflation-adjusted) return of a diversified U.S. stock portfolio. Bonds historically return 2-3% real; cash returns about 0%. If you are heavily in bonds or holding cash for safety, lower the assumed return — the future-value math is brutally sensitive to small differences. A 7% return over 30 years grows $1 to $7.61. A 5% return grows it to only $4.32. The 2-percentage-point gap costs you 43% of your nest egg.
When to use it
Run this calculator any time you change your contribution amount, get a raise, or rebalance your investment mix. The single biggest lever for retirement readiness is contribution rate — much more than picking the right index fund or shaving a tenth of a point off your expense ratio. If you can get from 6% to 12% of gross income, you are setting yourself up to retire a decade earlier than the average household.
It is also the right tool for sanity-checking the 4% rule. The 4% rule (originally Bengen's research, refined by the Trinity study) says a portfolio of 50-75% stocks and the rest bonds, withdrawn at 4% of starting value (adjusted for inflation each year) had a low historical probability of running out over 30 years. Multiply your retirement goal income by 25 to get the nest egg you need (the inverse of 4%). Want $80,000/year? You need $2 million.
Common mistakes
- Assuming your past return continues. The 1980-2020 U.S. stock market was historically excellent. Do not bake 11% nominal returns into a 30-year plan — most academic research projects 5-7% real going forward.
- Forgetting taxes and Social Security. The future-value number is gross. Withdrawals from traditional 401(k)s and IRAs are taxed as ordinary income. Roth withdrawals are not. Social Security benefits typically replace 30-40% of pre-retirement income — back that out before doing the 25× math.
- Ignoring inflation. If you assume a 7% nominal return and forget that 2-3% of it is just keeping pace with inflation, your "future value" is overstated in today's dollars. Either work in real (inflation-adjusted) numbers throughout, or run a separate inflation calculation on the result.
- Front-loading contribution growth. "I'll save more once I make more" rarely happens. Contributions made in your 20s and 30s are doing 90% of the heavy lifting because they have the longest runway to compound.
- Treating home equity as retirement savings. Your house is not a retirement account. You still have to live somewhere when you retire. Plan as if home equity is zero.
Frequently asked questions
How much do I need to retire?
A common rule is 25× your desired annual retirement spending — i.e., the inverse of the 4% rule. To spend $80,000 per year safely, you need about $2 million invested in a balanced portfolio. Subtract expected Social Security and pension income before applying the multiplier.
What rate of return should I assume?
For a U.S. equity-heavy portfolio, 6-7% real (inflation-adjusted) is a defensible long-run assumption. For a 60/40 stock/bond portfolio, 4-5%. For cash or short-term bonds, 0-1%. The default 7% in this calculator assumes you are mostly in stocks for the long term.
Is the 4% rule still safe?
Most analyses still find the 4% rule has a high success rate over 30-year retirements with 50-75% stock allocations. Newer research suggests 3.3-3.7% may be safer for early retirees with 40+ year horizons, or for portfolios starting at high valuations. The principle holds: starting withdrawal rate matters more than market timing.
Should I include Social Security in my retirement plan?
Yes, but conservatively. Current law projects benefits to be reduced to about 77% of full benefit by 2034 if Congress takes no action. A reasonable plan assumes 75-100% of your statement amount, depending on your age and political risk tolerance. Run the math both ways.
When should I start saving for retirement?
Now. A dollar saved at 25 is worth about 7× a dollar saved at 45 over a 40-year horizon (at 7% real returns). The 20s-and-30s contributions do most of the compounding work. If you have employer matching, contribute at least enough to capture the full match — that is a 50-100% instant return.