When can I retire? A free calculator that gives you a month, not a rule of thumb.

Most retirement calculators answer a question about a number: how much you need, or what you can spend. The question people actually carry around is when they can stop working. I built a free calculator that answers that one, from five numbers and no signup, and here is how to read what it tells you, what moves the answer, and what it leaves out.

What does the calculator ask for?

Five numbers: your age, the age you would like to retire, what you have saved across all accounts, what you add each year until you stop, and what you spend each year in retirement. There is one optional sixth, your monthly Social Security benefit at 67, which starts at $2,170, the average retired-worker check the Social Security Administration expects to pay in January 2027 (SSA, 2027 COLA fact sheet, as used in our COLA post). Your own figure is on your my Social Security statement, and it is worth using.

The retirement age is only used to show the chance of success for that year. The dates themselves come from testing every year you could retire in, starting now.

What month does a typical household get?

The calculator opens with this household: age 58, $1,200,000 saved, $30,000 added each year until retirement, $70,000 spent each year. As of October 31, 2026, the earliest month that keeps a 90% chance the money lasts to age 95 is October 2029, about 35 months away.

Asking for more certainty moves the date later, because a safer plan needs a bigger cushion against bad markets. Here the step from 85% to 95% adds 2 years and 5 months. The date comes from the chance of success for each retirement year, which the calculator draws as a table:

Take 90%. The chance is 87% for a start on January 1, 2029 and 91% for January 1, 2030, so 90% falls partway through that year, and rounding up to a month start gives October 2029.

Which number moves the date most?

Spending. Changing one number at a time on the default household, $10,000 a year less spending brings the 90% date forward 29 months and $10,000 more pushes it back 25. For comparison, $200,000 more or less in savings moves it 22 months earlier or 25 later, doubling or stopping what you add each year moves it 9 months earlier or 18 later, and Social Security of $3,000 or $1,500 a month instead of $2,170 moves it 18 months earlier or 16 later.

That is why the first question the calculator asks you to be honest about is spending. If your spending number is a guess, your date is a guess with a nice format. How to build your spending number from your bank statements walks through it, and how much you need to retire shows the same effect on the savings target.

Which confidence level should I pick?

The three levels are how much cushion you want against bad markets. At 90%, the money ran out before age 95 in about one simulated market history out of ten. That is not a prediction that you will be in the ten, and it is not a guarantee about the other nine. Treat 90% as the middle and look at the gap to 85% and 95%: the gap is the cost of certainty, in months, and it is often more informative than any single date. How spending can flex changes the picture too; see guardrails for the rules that let a plan start earlier by agreeing to cut in a bad market.

Why a month and not a day?

The engine answers in whole years: for each year you could retire, how likely the money is to last. The month comes from drawing a straight line between two years, and it is rounded up to the start of a month so the date never promises more than the numbers give. Markets move in years, not months, so June is not meaningfully different from July. The full version of this idea, with a day count and a dial, is described in the retirement countdown post.

What does the calculator assume, and what does it leave out?

• One person, filing single, planning to age 95.
• The portfolio is split 60% traditional (pre-tax), 15% Roth, 20% taxable and 5% cash, invested 60% in stocks. What you add each year goes into the pre-tax account until you stop.
• Social Security is claimed at 67.
• Included: federal income tax, Medicare and pre-65 health insurance costs, required minimum distributions, and a long-term-care cost late in life.
• The 10% early-withdrawal tax is included. The IRS says early distributions are generally those taken before age 59½ and carry a 10% additional tax unless an exception applies (IRS Topic no. 557). The calculator charges it on traditional money drawn before then. It does not model exceptions such as the Rule of 55 or a 72(t) schedule (how 72(t) schedules work), so if one applies to you the true date could be earlier.
• Left out: state tax, a spouse, pensions, rental income, your home and debts, and Roth conversions.

The full planner models all of those against your real accounts, and shows what moves your date: spending a little less, claiming Social Security later, saving more. The calculator is the quick version, with 400 simulated market histories per year instead of 2,000, so expect a rough answer.

Does the calculator save my numbers?

No. The numbers are sent to our server to run the simulation and are not stored. If you ask for the results by email, we store your email address and that you used the tool, not your numbers. We do not share your email.

How were these numbers calculated?

• Household: age 58, $1,200,000 saved, $30,000 added each year until retirement, $70,000 spent each year; retiring at 62; Social Security $2,170 a month at 67; the account split and assumptions above.
• Engine: the same function the calculator's server runs, 400 simulated market paths for each retirement year, a fixed seed so the same inputs always give the same answer, with the chance kept from falling as the year moves out. A small dip between years would be simulation noise.
• Dates: this year's chance is placed on today and each later year's on January 1, with a straight line between them, rounded up to the next month start. Computed as of October 31, 2026; because this year's point is today, a date before next January depends on the day it is computed.
• Sensitivity table: one number changed at a time from the base household, everything else unchanged.

Frequently asked questions

How do I find the earliest date I can retire?

Test every year you could retire in: for each, simulate many market histories with your savings, spending, taxes, Social Security and health costs, and count how often the money lasts to 95. The earliest year that reaches the chance you want is your date. The free calculator does this from five numbers and reads the month off a straight line between years. For a household aged 58 with $1,200,000 saved, adding $30,000 a year and spending $70,000, the 90% date is October 2029.

What does a 90% chance mean?

It is the share of simulated market histories in which the money lasts to age 95. At 90%, it ran out in about one history out of ten. It measures how much cushion a plan has, not whether it will work.

Which input changes the date the most?

Spending. On the default household, $10,000 a year less spending brings the 90% date forward by 29 months and $10,000 more pushes it back 27 months, about as much as $200,000 of savings in either direction (22 and 25 months).

Does the calculator include the 10% early-withdrawal tax?

Yes, on traditional money drawn before 59½, as the IRS describes in Topic no. 557. It does not model exceptions such as the Rule of 55 or 72(t).

Is the calculator free, and are my numbers saved?

It is free, with no signup. Your numbers are used to run the simulation and are not stored. If you ask for the results by email, only your email address and that you used the tool are kept.