Roth IRA Savings Calculator

How it works

A Roth IRA is an ordinary investment account with one unusual promise attached. You fund it with money you have already paid income tax on, so nothing is deducted on the way in, and in exchange qualified withdrawals in retirement come out completely untaxed. That makes the growth math the plain compound-growth math, with no hidden deduction waiting at the end. This calculator grows the balance you already hold forward for the full timeline, then adds the future value of every monthly contribution, assuming end-of-month deposits and monthly compounding:

• B — your Roth IRA balance at retirement
• P — the Roth balance you hold today
• M — what you contribute each month
• i — monthly return (annual rate ÷ 12)
• n — months until you retire

With the defaults above, the $15,000 already in the account grows to about $85,881 on its own over 25 years at 7%, while $500 a month builds another $405,036, for a balance near $490,917. Split that and $150,000 is money you put in while $325,917 is growth. The upper band on the chart is that growth, the part you never contributed and, under the withdrawal rules, never hand back.

The projection uses only the four numbers you enter and a steady return. It does not enforce the annual contribution limit, check your income against the phase-out rules, or model your tax situation, so read the balance as a planning estimate rather than a promise.

✓ Every result is checked against independent reference math. See how we test the calculators →

A worked example: $500 a month into a Roth IRA for 25 years

Say you already have $15,000 in a Roth IRA and you set up a $500 automatic transfer for the first of every month. Twenty-five years at a 7% return later, the account holds $490,917. You contributed $150,000 of that yourself. The other $325,917 is growth, and because the tax was settled on the way in, every dollar of it is yours to spend.

The transfer is the lever you control. Raise it to $700 and the same 25 years at the same 7% finish at $652,931. You paid in $210,000 rather than $150,000, an extra $60,000 spread thinly across the whole stretch, and the ending balance climbed by $162,014. Two hundred dollars a month bought back nearly three times itself, because each of those dollars still had decades left to compound.

Nothing clever is happening here. It is one automatic transfer, left alone, inside an account whose entire feature is that the IRS has already been paid. Enter your own balance, your own monthly amount, and the years you have left, and see what your version of the number looks like.

Why this balance is the honest one

Nearly every retirement projection carries a hidden asterisk, and the Roth is the one place it does not apply. Run the same $500 a month through a traditional IRA or a pre-tax 401(k) and the chart looks identical, because the compounding is identical. The difference only shows up on the day you withdraw.

A pre-tax balance is shared with the IRS. Withdrawals arrive on your tax return as taxable income, so the headline figure overstates what you can genuinely spend by whatever your tax rate turns out to be decades from now. Nobody knows that rate. It depends on tax law that has not been written yet and on an income you have not earned yet, which makes every pre-tax projection an estimate wrapped around a guess.

A Roth removes the guess. You settled the bill on the way in, at a rate you already know, so $490,917 at the defaults means $490,917 of spending money. That certainty is the whole product, and it is worth paying for even in the years when the deduction you gave up would have felt good, because a plan built on a known number is a plan you can act on.

Your contributions can come back out. The growth cannot.

The Roth has a second feature almost nobody uses on purpose and plenty of people discover in a panic. The money you contributed directly is yours to withdraw at any time, at any age, with no tax and no penalty. You already paid tax on those dollars, so the IRS has no further claim on them. At the defaults that is the $150,000 line in the breakdown, reachable in an emergency without a form justifying why.

Earnings are a different animal. To take the growth out cleanly you generally need to be at least 59½ and to have had a Roth IRA open for at least five years. Miss either test and the earnings portion can be taxed and hit with an early-withdrawal penalty, with only a short list of exceptions.

That combination makes a Roth a reasonable last-resort backstop and a terrible piggy bank. The $150,000 you contribute only becomes $490,917 because it sat still for 25 years. A dollar pulled out in year ten does not simply leave, it takes fifteen years of compounding with it, and because the annual limit resets each year you usually cannot put it back.

The limit and the income rules move every year

Two IRS rules sit outside this calculator, and both are left out on purpose, because both change.

The first is the annual contribution limit. There is a cap on what you may put into an IRA each year, it is adjusted for inflation most years, and a larger allowance opens up once you reach the catch-up age. This tool will happily project $2,000 a month for you, so look up the current year’s figure on irs.gov before building a plan around a contribution the account will not accept.

The second is the income phase-out. Above a certain income your allowed contribution shrinks, and above a higher one it falls to zero. Those thresholds also move each year and depend on how you file.

Neither rule is a dead end. If the monthly amount you want sits above the cap, fund the Roth to the limit and route the remainder into a workplace plan or a plain taxable brokerage account. If your income has grown past the phase-out, the Roth option inside a workplace plan carries no income test at all, which is why higher earners often end up holding their Roth money there instead.