A Roth IRA is a retirement account you fund with after-tax dollars — and the powerful part is that all the growth, and your eventual withdrawals in retirement, are completely tax-free. That makes decades of compounding especially valuable, because none of it is shared with the IRS later.
The default models about $583 a month (roughly the annual contribution limit spread over the year) at 7% for 30 years. Adjust it to your own contributions and timeline.
Why a Roth IRA supercharges compounding
In a regular taxable account, you can owe tax on dividends and gains along the way, which quietly drags on compounding. In a Roth IRA, nothing is taxed inside the account and qualified withdrawals in retirement are tax-free. So the entire balance the calculator shows is money you actually get to keep.
Because the benefit is on the growth, the longer your money compounds, the more a Roth is worth relative to a taxable account. Starting in your twenties versus your thirties can mean a dramatically larger tax-free sum — exactly the “cost of waiting” the visualizer below makes concrete.
Contribution limits and time horizon
The IRS caps annual Roth IRA contributions (in recent years, $7,000, or $8,000 if you're 50 or older), and eligibility phases out at higher incomes. This calculator doesn't enforce those limits — it simply projects whatever contribution you enter — so keep the current cap in mind when you set your monthly amount.
Because the limit is modest, time is your most important lever. Maxing a Roth consistently from a young age is one of the most reliable paths to a seven-figure retirement balance, even though the yearly contribution feels small.
What steady contributions could become
Contributing near the limit every year at a 7% long-run return can grow into a substantial tax-free nest egg over a working lifetime, with the majority of the final balance coming from growth rather than your deposits. The interest-versus-contributions split in the results makes that ratio obvious.
Remember this is a projection at an assumed average return, not a guarantee. Markets vary; use the likely-range toggle and the “in today's money” view to keep your expectations grounded.
Frequently asked questions
How much will my Roth IRA grow?
It depends on how much you contribute, your return, and your time horizon. As an example, about $583 a month at 7% for 30 years can grow to well over half a million dollars — all tax-free. Enter your own numbers above for a personalized projection.
What is the Roth IRA contribution limit?
In recent years the annual limit has been $7,000, or $8,000 if you're 50 or older, with eligibility phasing out at higher incomes. Limits change over time, so check the current year's figure when planning.
Is a Roth IRA worth it?
For most long-term savers, yes — tax-free growth and tax-free retirement withdrawals are valuable, especially if you expect to be in a similar or higher tax bracket later. The longer your money compounds, the bigger the advantage.
Can you become a millionaire with a Roth IRA?
Yes. Consistently contributing near the limit from a young age at a reasonable long-run return can compound into seven figures by retirement — and because it's a Roth, that balance is tax-free.
Worked examples
Each example below shows inputs fed directly into the compound interest engine. Every figure in the stat grid is computed at build time from those inputs, never hand-typed.
Max Roth IRA contributions for 30 years
Starting at $0, contributing approximately $583/month (≈$7,000/year) at 7% compounded monthly for 30 years.
Maxing out a Roth IRA at roughly $583/month for 30 years at a 7% return produces about $711,243 — from only $209,880 in contributions. The $501,363 in tax-free growth is the Roth IRA's core advantage: you pay income tax now, and all growth is never taxed again.
Consistent Roth IRA saver, 25 years
Starting at $0, contributing $583/month at 7% compounded monthly for 25 years.
Twenty-five years of Roth IRA contributions at $583/month grows to roughly $472,272, against $711,243 at 30 years — a $238,971 difference from just five extra years of compounding, on only $34,980 of additional deposits.
More questions answered
How much does a Roth IRA grow in 30 years?
If you contribute the 2024 maximum of $7,000/year ($583/month) for 30 years at 7% compounded monthly, your Roth IRA grows to roughly $661,000 — from $210,000 in contributions. The $451,000 difference is tax-free growth. At a 10% return the ending balance reaches about $1.32 million from the same contributions. Time and rate are both critical; start as early as possible.
Can I model a Roth IRA with a starting balance?
Yes — if you are rolling over a balance or already have funds in the account, enter the current balance as the starting principal. The calculator models the compounding of both the existing balance and ongoing contributions from the current date forward.
Method and assumptions
This calculator projects a balance from the inputs you give it. It is an arithmetic model, not a forecast, and not financial advice — a real account’s return varies year to year while this projection holds your rate constant.
- Period-by-period, not a formula
- The balance is stepped forward one compounding period at a time rather than evaluated with a closed-form equation. That is what makes the year-by-year breakdown real numbers from the same run you see at the top, rather than a separate approximation.
- How the periodic rate is derived
- Your annual rate is divided by the number of compounding periods in a year — a 6% rate compounded monthly applies 0.5% each month. This is the standard convention, and it is why the nominal rate and the APY are not the same number: compounding those twelve 0.5% steps produces slightly more than 6% over the year.
- When contributions land
- Contributions are spread evenly across every compounding period and deposited at the end of each one, after that period’s interest has accrued — the ordinary-annuity convention most calculators use. Depositing at the start of each period instead would produce a slightly higher balance, so treat this projection as the conservative side of that choice.
- Inflation adjustment
- The “in today’s money” figures deflate the balance by your inflation rate compounded annually. Contributions are shown in the dollars you actually deposit, so the inflation-adjusted interest figure is the real terminal value minus what you put in — not a separately deflated interest total. See nominal versus real figures for the distinction.
- Time to double
- The doubling figure describes your rate alone — how long a balance takes to double with no further deposits. It deliberately ignores contributions, because mixing them in would measure your savings habit rather than the return; the Rule of 72 is the mental shortcut for the same number.
- What is not modelled
- Taxes, account fees, fund expense ratios, and any penalty for early withdrawal are all excluded. Returns are assumed constant rather than variable, so no sequence-of-returns risk is captured. A taxable account will trail these figures; a tax-advantaged one will track them more closely.