Seeing where your savings could land
Retirement planning comes down to four levers: how long your money has to grow, how much you add each month, the return it earns, and how inflation erodes the end figure. Set your current and target ages, your starting balance, a monthly contribution, an expected annual return, and an inflation rate, then calculate to see your projected nest egg — shown both as the raw nominal number and as what it would actually buy in today's dollars — alongside a year-by-year chart of the climb.
Saving $500 a month for 30 years at 7%
Picture a saver who starts from $0 and puts away $500 a month from age 35 to 65 — 30 years — earning a 7% annual return compounded monthly. By retirement they have contributed $180,000 of their own money, yet the balance reaches roughly $609,986. The extra ~$430,000 is pure compound growth — more than twice what they put in — which is what three uninterrupted decades in the market can do.
The Power of Compound Interest
Compound interest means your investment returns themselves earn returns. The longer your money is invested, the more pronounced this effect becomes. A 30-year-old who invests $500 per month at 7% will accumulate far more than someone who starts at 40 and doubles their contribution — time in the market is often more valuable than the size of the contribution. This calculator uses the standard future-value formula:
FV = PV × (1 + r)^n + PMT × [((1 + r)^n − 1) / r]
Where PV is your current savings, r is the monthly return rate (annual rate ÷ 12 ÷ 100), n is the number of months to retirement, and PMT is your monthly contribution.
Understanding the 4% Rule
The 4% rule, derived from the landmark Trinity Study, is the most widely used retirement withdrawal guideline. It states that if you withdraw 4% of your portfolio in year one of retirement and adjust each year for inflation, your portfolio has historically survived at least 30 years in the vast majority of historical market scenarios. Practically, this means:
How much do you need?
Multiply your expected annual retirement expenses by 25 to estimate your target nest egg. If you plan to spend $60,000 per year, you would aim for a $1,500,000 portfolio. Use this calculator to find out when you might reach that milestone.
Is 4% always safe?
The 4% rule was developed using US stock and bond data from 1926 onwards. Some financial planners suggest a 3–3.5% withdrawal rate for extra safety, especially for retirements lasting 40+ years or in a lower-return environment. The key insight remains: the larger your portfolio relative to your spending, the greater your financial security.
When Should You Start Saving?
The answer is: as early as possible. Consider two savers, both targeting retirement at 65. Saver A starts at 25, contributes $400 per month, and stops at 35 — just 10 years of contributions. Saver B starts at 35 and contributes $400 per month all the way to 65 — 30 years of contributions. Assuming 7% annual returns, Saver A will likely end up with more money than Saver B, despite contributing for only one-third as long. This is the magic of starting early and letting compound interest run for decades.
Inflation and Purchasing Power
A nominal balance of $1,000,000 in 30 years is not the same as $1,000,000 today. At 2.5% annual inflation, that future million is worth roughly $477,000 in today's purchasing power. This is why this calculator shows both your nominal balance (the raw number in your account) and your inflation-adjusted balance (what that money is worth in today's dollars). Planning with the real value gives a more honest picture of your retirement readiness.
What a single projection can't tell you
This is a straight-line projection, and reality is anything but straight. It applies one fixed return every single month, so it cannot capture the order in which good and bad years arrive — and a market crash early in retirement does far more damage than the same crash late, a hazard known as sequence-of-returns risk. It also leaves out the taxes you will owe on withdrawals from a traditional account, the fund fees that quietly skim your return each year, and any change to your contributions, salary, or Social Security along the way. Read the result as one plausible scenario for comparing choices, not a promise of the number you will retire on.
Retirement planning questions
How much do I need to save for retirement?
A common guideline is to save 10–15% of your gross income throughout your working life. The exact amount depends on your desired retirement income, expected Social Security benefits, retirement age, and life expectancy. Many financial planners suggest accumulating 25 times your annual retirement expenses — a figure derived from the 4% rule. Use a retirement calculator with your specific numbers to get a personalized projection.
What is a good rate of return to expect for retirement savings?
Historically, a diversified stock portfolio has returned roughly 7–10% per year before inflation (about 5–7% after adjusting for inflation). A balanced portfolio of stocks and bonds might return 5–7% nominally. Conservative projections often use 6% nominal or 4% real (inflation-adjusted) for long-term planning. The appropriate rate depends on your asset allocation and risk tolerance.
When can I retire?
You can retire when your savings are large enough to sustain your desired lifestyle. The key factors are: your expected annual expenses in retirement, how many years you need your savings to last (typically 20–30 years), your expected investment return during retirement, and other income sources like Social Security or a pension. The 4% rule is a popular starting point: if your portfolio is at least 25 times your annual expenses, many people consider that enough to retire.
What is the 4% rule?
The 4% rule is a retirement withdrawal guideline derived from the Trinity Study. It states that if you withdraw 4% of your portfolio in the first year of retirement and adjust that amount for inflation each subsequent year, your portfolio has historically lasted at least 30 years in most market conditions. This means a portfolio of $1,000,000 would support roughly $40,000 per year in spending. The rule is a useful starting point, but not a guarantee — sequence-of-returns risk, higher spending needs, or very long retirements may require a lower withdrawal rate.