Retirement Calculator

What this Retirement Calculator does

This English-language retirement calculator projects how your savings grow from today to your target retirement age, accounting for your monthly contributions and an expected annual return. Most retirement planners hand you one number — a nominal future balance — and leave you guessing what it actually buys. This tool goes further: it reports your balance in both nominal future dollars and real inflation-adjusted today's dollars side by side, then applies the 4% safe withdrawal rule to translate that balance into a sustainable monthly income estimate. Whether you're stress-testing a 401k plan, sketching a Roth IRA trajectory, or comparing retiring at 60 versus 65, those three numbers together give you a honest picture. 100% client-side — your data never leaves your browser. No uploads, no tracking, no server logs.

Features

• Nominal vs. real balance. Displays your projected balance in future dollars alongside its inflation-adjusted equivalent in today's purchasing power, so you're never misled by a large nominal figure that inflation has quietly eroded.
• 4%-rule monthly income. Applies the widely cited safe withdrawal rate to your projected balance and shows the monthly income that balance could sustainably support — a number most calculators bury or omit entirely.
• Compound growth projection. Models compound interest across the full accumulation period. Even small differences in annual return or contribution amount compound dramatically over decades, and the chart makes that visible. For deeper compounding math, the [compound interest calculator](/en/compound-interest-calculator/) covers the underlying mechanics.
• Flexible inputs. Accepts current age, target retirement age, current savings balance, monthly contribution, expected annual return, and an inflation rate — all adjustable so you can run multiple scenarios quickly.
• Instant scenario comparison. Change a single input — retirement age, monthly contribution, or return rate — and results update immediately. Comparing retiring at 60 versus 65 is a matter of one edit, not a new form submission.
• No account, no tracking. All calculations run in your browser. Nothing is sent to a server, stored in a database, or tied to an email address. The Knight Capital incident postmortem is a reminder of how badly things can go wrong when financial data moves through systems that weren't designed for it — this tool avoids that entirely.

How to use the Retirement Calculator

Fill in the six fields and click Calculate. Results appear instantly — no page reload required.

1. Enter your current age and retirement age. Type your current age and the age at which you plan to retire. The difference is your accumulation period — every extra year has an outsized effect thanks to compound growth.
2. Enter current savings and monthly contribution. Add your existing retirement balance (401k, Roth IRA, or total across accounts) and your planned monthly contribution. Include any employer match in the monthly figure if it's consistent.
3. Set return and inflation rates. A long-run nominal return of 6–7% is a common conservative estimate for a diversified portfolio. Set inflation to 2.5–3% for a realistic real-dollar result. Avoid assuming 10%+ — that's a ceiling, not a midpoint.
4. Read the three outputs. The tool shows (1) nominal future balance, (2) inflation-adjusted balance in today's dollars, and (3) estimated sustainable monthly income based on the 4% rule. Focus on number 2 to set a realistic spending target.
5. Run alternative scenarios. Adjust retirement age by five years or bump monthly contributions by $200 and recalculate. The delta between scenarios is often more useful than any single projection.

Common use cases

• Validating your savings rate. Check whether your current monthly contribution gets you to a target balance by retirement age, or how much you'd need to add each month to close the gap. A quick sanity check before a meeting with a retirement advisor.
• Comparing early vs. standard retirement. Run the same inputs at retirement ages 60, 65, and 70 to see how five extra years of compounding — and fewer years of drawdown — shifts your monthly income estimate. The difference often dwarfs any realistic tweak to return rate.
• Translating a balance target into monthly income. If you have a number in mind — say, $1.2 million — the 4%-rule output converts that directly into a monthly income figure, letting you test whether it actually covers your expected expenses in New York or Toronto.
• Modeling the value of an employer match. Add the employer match to your monthly contribution figure and compare the result against contributing without it. For many people, capturing the full match is the single highest-return financial move available to them.
• Stress-testing against inflation. Raise the inflation input from 2.5% to 4% and watch the real-dollar balance drop. This is exactly the scenario long-term retirement planners worry about, and seeing the number directly is more persuasive than any general warning.

Frequently asked questions