Free Roth IRA Calculator

Your Roth IRA Projection

The results card updates as you type. As a Roth IRA retirement calculator it reports three things, and the second is the one most people underestimate.

Below those sits the comparison line, which sets your Roth result against an equivalent traditional IRA using the two tax rates you entered. It reports which way the arithmetic falls; it does not tell you which account to open.

Until you enter a return, only the contribution figures appear — those are arithmetic and need no assumption. Everything growth-dependent stays blank, because this page will not invent a market return on your behalf. Open View Full Breakdown to see both accounts side by side, including the traditional balance before and after withdrawal tax.

What Is a Roth IRA?

A Roth IRA is an individual retirement account you open yourself, with a provider of your choosing, funded with money you have already paid income tax on. There is no deduction for contributing. In exchange, the account grows without annual tax on gains, and qualified withdrawals in retirement are not taxed at all.

That is the whole bargain in one sentence: pay the tax now, so you do not pay it later. A traditional IRA offers the reverse deal.

Features worth knowing before you open one:

• It is yours, not your employer's. Changing jobs does not affect it, and the investment choice is generally far wider than a workplace plan's menu.
• Contributions and earnings are treated differently on withdrawal. The money you put in can generally come out at any time; the growth is subject to additional conditions.
• Eligibility depends on income. The ability to contribute directly phases out above thresholds the IRS sets and updates.
• There is an annual contribution cap, also set by the IRS, which applies across all your IRAs combined rather than per account.

This page is a tax-free growth calculator for the accumulation phase. For the wider question of whether all your retirement savings together produce enough income, use our retirement calculator.

How Roth IRA Growth Works

Mechanically, a Roth IRA growth calculator does the same compounding arithmetic as any other investment projection. What differs is what happens at the end.

Money goes in after tax. It is invested, and the gains compound without being taxed each year — no annual bill on dividends or realized gains inside the account, which is itself a meaningful advantage over an ordinary taxable account. Then, provided the qualifying conditions are met, the whole balance comes out without income tax.

The consequence is worth stating plainly. In a taxable account, the growth is eventually reduced by tax. In a traditional account, the growth is taxed on withdrawal along with everything else. In a Roth, the growth is the part you keep entirely — and over a long horizon, the growth is usually larger than everything you contributed.

The table below uses your own figures — your starting balance, your time frame, your assumed return — and varies only the monthly contribution, so you can see how the tax-free portion scales:

Notice that the third column grows faster than the second as the contribution rises. Every extra dollar gets the full remaining time to compound, and in a Roth none of that compounding is ever taxed.

Two honest caveats. The word qualified is doing real work: withdrawals must meet both an age condition and a holding-period condition to be fully tax-free, which is covered in the FAQ below. And none of this protects you from investment risk — a Roth wrapper does not make a losing investment profitable.

Roth vs Traditional IRA: The Tax Trade-off

This is the question a Roth vs traditional IRA calculator exists to answer, and it has a cleaner answer than most people expect — though not the one usually advertised.

The result that surprises people: if your tax rate is the same now and in retirement, the two accounts produce an identical after-tax outcome. Not similar — identical. Paying tax before compounding or after compounding gives the same answer when the rate does not change, because multiplication does not care about order.

That only holds if the comparison is fair, and this is where most published comparisons go wrong. Putting the same nominal dollar amount into each account flatters the Roth, because a traditional contribution is made with pre-tax money — the same out-of-pocket cost buys a larger traditional contribution. Our calculator grosses the traditional contribution up accordingly, so the two are compared at equal cost to you.

Since nobody knows their future tax rate with certainty, holding some of each is a common response to that uncertainty rather than a hedge we are recommending. Other factors — deductibility, required distributions, estate planning — also differ between the two, and a tax professional is the right person to weigh them for your situation.

Income and Contribution Limits

Two separate limits apply to Roth IRAs, and they work differently. Both are set by the IRS and adjusted over time, which is exactly why no figure for either appears anywhere on this page.

The phase-out is gradual rather than a cliff: within the range, the amount you may contribute is reduced rather than eliminated. Which figures apply to you also depends on your filing status and on whether you or a spouse are covered by a workplace plan.

We will not print the numbers. Any figure published here would eventually be wrong, and a stale income threshold is the kind of detail that causes a genuine problem — an excess contribution has to be corrected and can carry a penalty. Check the current thresholds on the IRS Roth IRA contribution page and the general IRS retirement plans pages before contributing.

Note too that the calculator above applies no limit at all to what you enter. It projects whatever contribution you type, which makes it useful for scenarios but means it will not warn you if a figure exceeds what you are actually permitted to contribute.

Roth IRA vs 401(k): Which Comes First?

These are different kinds of account rather than competing versions of the same thing, and most people end up using both. The ordering question, though, has a widely accepted answer.

Capture the employer match first. If your workplace plan matches contributions, that match is part of your compensation and is an immediate return on the money you defer, before any investment growth. No feature of a Roth IRA competes with collecting money you would otherwise forgo. Our 401(k) calculator shows whether your current contribution rate captures the full match and what it is worth over a career.

After the match, the comparison turns on fees, investment options and tax treatment rather than any universal rule. A Roth IRA's wider choice and tax-free qualified withdrawals appeal to many savers; a 401(k)'s higher cap and absence of income limits matter more to others. Both caps and thresholds come from the IRS.

How to Use This Roth IRA Calculator

1. Enter your current Roth IRA balance, or leave it at zero if you are starting out.
2. Set your monthly contribution. Remember this is after-tax money, and that the IRS caps the annual total across all your IRAs.
3. Choose an assumed annual return. The field is blank by design. Run a cautious figure as well as an optimistic one.
4. Set your current and retirement ages to define the growth period.
5. Enter your tax rate now and your expected rate in retirement. These drive only the comparison, not the Roth projection itself.
6. Read the tax-free growth figure, then the comparison verdict, then open the full breakdown for both accounts side by side.

The most instructive thing you can do here takes ten seconds: set both tax rates to the same number and watch the comparison land on a tie. Then raise the retirement rate and watch the Roth pull ahead. That single experiment explains the entire Roth-versus-traditional debate better than any article can.

Bear in mind what the tool does not model: investment fees, the five-year rule, required distributions on the traditional side, state taxes, and any IRS limit on what you enter. Nothing you type is stored or sent anywhere.

Our Methodology

The Roth balance uses the standard future-value formula for a lump sum plus a regular deposit, compounded monthly: FV = P(1+r)ⁿ + M × ((1+r)ⁿ − 1) ÷ r. Tax-free growth is that balance minus everything contributed. No tax is applied to the Roth result, which is the point of the account.

The traditional comparison is the part that needs explaining. Comparing an equal nominal contribution in each account is misleading, because a traditional contribution is made with pre-tax money — the same out-of-pocket cost buys a larger contribution. We therefore gross the traditional deposit up by your current tax rate, project it, then apply your expected retirement rate to the whole withdrawal. That is an equal-cost comparison, and it is why the verdict reads "line ball" when both rates match: algebraically, C/(1−t) × (1+r)ⁿ × (1−t) = C(1+r)ⁿ.

Before publication the growth engine was cross-checked against an independently written month-by-month simulation and reproduced published annuity values exactly. The Roth/traditional equivalence was confirmed at four unchanged tax rates, and the direction of the result held across twenty-four horizon and return combinations with no exceptions. The contribution-versus-earnings split was verified exact for every year from one to thirty. All currency is rounded to cents before display.

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