About the Roth IRA Calculator
A Roth IRA is a US retirement account where you pay tax on the money you put in, but the growth and qualified withdrawals are tax-free. This Roth IRA calculator projects what your account could be worth from a starting balance, a yearly contribution, a number of years and a rate of return, and compares it with putting the same money into an ordinary taxable account where the gains are taxed. The difference shows the value of the tax-free growth. It is a simple educational model: real accounts have contribution limits, income limits, withdrawal rules and tax rules that change over time.
Updated October 2026
How to use the Roth IRA Calculator
- 1Enter your starting balance and how much you will contribute each year.
- 2Enter the number of years until you withdraw.
- 3Enter the return you expect per year.
- 4Enter the tax rate on gains you would pay in a regular account.
- 5Read the Roth IRA balance, the regular account balance after tax and the tax avoided.
A worked example
Contribute 6,000 at the start of each year for 30 years at 7 percent, with nothing to begin with. You put in 180,000 and the account grows to about 606,000, so growth is roughly 426,000. In a taxable account taxed at 15 percent on gains, you would pay about 64,000 in tax and be left with around 542,000. The Roth's advantage is about 64,000, or around 12 percent higher, in this simple model.
Points to consider
- The tax-free benefit is larger the longer you invest and the higher your returns.
- Withdrawal rules matter: taking out earnings early can mean tax and penalties.
- Employer plans, such as a 401(k) with a match, often come first.
- A higher tax rate on gains makes the Roth more valuable.
- Keep contributions within the yearly limit.
Related tools
The Compound Interest Calculator shows growth with any regular deposits, the Retirement Calculator plans a whole retirement, the Pension Calculator projects a workplace pot, the Mutual Fund Calculator shows the cost of fees and the Inflation Calculator shows what future money will buy. Treat the results as estimates and not tax advice.
Features
- Roth IRA balance after any number of years
- Comparison with a taxable account
- Tax avoided on the growth
- Total you put in and total growth
- Contributions made at the start of each year
- Up to 70 years
- Runs in your browser
Frequently asked questions
How does a Roth IRA work?
You contribute money you've already paid income tax on. Investments inside the account grow without yearly tax, and you can take out the contributions at any time and the earnings tax-free once you meet the rules, such as being over 59½ and having held the account for five years.
What is the difference between a Roth IRA and a traditional IRA?
With a traditional IRA, contributions may be tax-deductible now and withdrawals are taxed later. With a Roth, there is no deduction now but withdrawals are tax-free later. A Roth tends to suit people who expect to pay the same or higher tax in retirement, and a traditional one those who expect lower tax later.
What are the Roth IRA contribution limits?
There is a yearly limit that changes from time to time, with a higher limit for people over 50, and income limits that reduce or remove your ability to contribute at higher incomes. Check the current figures with the IRS or your provider before relying on a yearly amount.
How is the taxable account modelled?
Both accounts receive the same contributions and returns. The taxable account is simply charged tax at the end on the total gains at the rate you enter. In real life, dividends and gains may be taxed along the way and at different rates, so this is a simplified comparison.
What return should I assume?
Returns depend on how you invest and can be negative in some years. Many long-term planners use 5 to 7 percent for a diversified stock portfolio. Try several rates to see how the advantage changes, and remember that nothing is guaranteed.
Is this tax or investment advice?
No. It is a simplified projection for learning. Tax law and eligibility change and depend on your situation. Speak to a qualified tax adviser or financial planner before deciding.