Roth IRA Calculator
Tax-Free Growth Is Worth More the Longer It Runs
A Roth IRA trades an upfront tax break for a bigger one later: contributions go in after tax, but every dollar of growth — and every withdrawal in retirement — is tax-free, provided the account meets the standard holding requirements. Because the return rate matters so much over long horizons, small assumption changes shift the ending balance dramatically. This calculator projects that growth and checks your contribution against the current IRS annual limit.
The Formula
P is your current Roth IRA balance, PMT is your annual contribution, r is the annual return rate, and n is the number of years. For 2025, the IRS caps annual contributions at $7,000, or $8,000 if you're 50 or older; the calculator applies this cap automatically when an age is entered.
Where This Calculation Matters
- Maximizing tax-free growth — because withdrawals are untaxed, every dollar of investment growth in a Roth is worth more than the same growth in a taxable account.
- Early-career contributions — younger investors typically benefit most from a Roth, since decades of tax-free compounding outweighs the value of a near-term deduction.
- Estate and legacy planning — Roth IRAs have no required minimum distributions during the original owner's lifetime, making them useful for passing tax-free assets to heirs.
- Diversifying tax exposure — holding both pre-tax (401(k)/Traditional IRA) and after-tax (Roth) accounts gives more flexibility to manage taxable income in retirement.
Return Rate Sensitivity Over 30 Years
| Assumed annual return | Projected balance after 30 years |
|---|---|
| 5% | $465,071.93 |
| 7% | $661,225.50 |
| 9% | $954,152.77 |
Total contributions over 30 years at $7,000/year equal $210,000 in every scenario — the difference is entirely from compounding at different return rates.
How to Use This Calculator
- Enter your current Roth IRA balance.
- Enter your planned annual contribution.
- Enter the annual return rate you expect.
- Enter the number of years until retirement.
- Optionally enter your current age so the calculator can check your contribution against the IRS limit for your age group.
- Select Calculate to see your projected balance, total contributed, and total tax-free growth.
Related Calculations
Compare this against pre-tax growth with the 401(k) Calculator, or check current-year limits in detail with the IRA Contribution Calculator.