Retirement Calculator
Your age, what's saved, what you add monthly, an honest return — and the number you actually care about: what it's worth in today's dollars, plus the income it could pay.
Projection, not a promise · returns assumed steady (real markets aren't) · nothing you enter leaves this browser.
Spotted a mistake or have an idea? — errors get fixed and credited publicly.
Last reviewed: July 20, 2026 · Formulas verified by automated tests before every release.
How much will I have when I retire?
Future value = current savings compounded + monthly contributions compounded: $25,000 saved plus $500/month at 7% from age 30 to 65 grows to about $1.19M nominal — roughly $500K in today's dollars at 2.5% inflation, paying about $1,670/month by the 4% rule. Enter your real numbers above; the honest today's-dollars figure leads the results.
The only three levers
Every retirement projection moves on three dials: when you start, how much you add, and what the money earns. The brutal arithmetic is that the first dial dominates — a decade of delay costs roughly half the outcome at the same contribution, because compounding's steep end only arrives with years. The return dial is the one you control least, which is exactly why this calculator flags assumptions above 10%: hope is not an asset class. The contribution dial is the honest workhorse — and even cancelling a $30 subscription and routing it here adds five figures over a career.
Nominal flatters, today's dollars tell the truth
"A million dollars" in 2060 is not a million of today's dollars — at 2.5% inflation it buys what ~$420K buys now. Most retirement calculators lead with the big nominal number because it feels good; we lead with the deflated one because you'll be spending in future prices, not admiring a figure. The 4%-rule income line converts the nest egg into a monthly feel: what this pile could plausibly pay you, in money you understand. To play with the growth math itself, the compound interest calculator is the same engine unhooked from age; for the shorter climb to a known target, the savings goal calculator works backwards; and guaranteed-rate money belongs in the CD calculator.
Sources, assumptions and limitations
- Assumptions: Monthly compounding at a steady assumed return — real markets vary wildly year to year.Today's-dollars value deflates the nominal result by your inflation input.The 4% rule is a historical rule of thumb (Trinity study), not a guarantee; taxes are not modelled.Social Security, pensions and employer matches are outside this simple projection.Nothing you enter is stored or transmitted.
- Sources:
- Last reviewed: by the CalcNotebook team
Frequently asked questions
How much money do I need to retire?
The classic rule of thumb is 25× your desired annual spending — the flip side of the 4% rule: $40,000 a year of retirement spending suggests roughly a $1M nest egg in today's dollars. It's a planning anchor, not a law; taxes, pensions, Social Security and your actual spending shape the real number.
What return should I assume?
US stocks have averaged roughly 10% nominal (about 7% after inflation) over the last century — with brutal decade-long detours along the way. A 6–7% assumption for a diversified portfolio is common for planning; anything above 10% earns a warning here, because plans built on optimism retire late.
Is the 4% rule safe?
It's a rule of thumb from historical US data (the Trinity study): withdrawing 4% of the starting balance, inflation-adjusted, survived most 30-year retirements. It is not a guarantee — sequence-of-returns risk, longer retirements and today's valuations all argue for flexibility rather than autopilot.
Why show today's dollars?
Because $1,000,000 in 35 years buys what about $420,000 buys today at 2.5% inflation. Nominal numbers flatter; today's-dollars numbers tell you what your future actually feels like. We show both — the big honest number first.
When should I start saving?
The unhelpful-but-true answer: the earlier of now and yesterday. Starting at 25 instead of 35 roughly doubles the outcome at the same monthly amount — time is the only lever that works while you sleep. Run the numbers with your real age and see.
Do you store my numbers?
No. Ages, balances and results live only in this browser tab — nothing is uploaded or saved.