Tax-free · Monthly · Inflation-aware

Roth IRA Compound Interest

Project tax-free retirement growth with monthly contributions, decades of compounding, and the real-dollars number in today's purchasing power.

Load scenarioMax $7k/yr, 30y Start at 22, retire at 62 Catch-up at 50+

Live·Updates on every change

Inputs

Currency

Initial amount

Annual interest rate

Time horizon

Years:

Months:

Compound frequency

Regular contributions: (optional)

Deposit amount: (optional)

Annual deposit increase? (optional)

Inflation & tax⌄

Annual inflation rate

Shown as a "real" value in today's money.

Tax on gains

Applied once at the end of the horizon.

Future value

—

After

—

Contributed

—

Principal + deposits

Interest earned

—

Effective APY

—

Growth over time

Principal, contributions, and interest — stacked year by year.

PrincipalContributionsInterest

Year-by-year breakdown

Opening balance, deposits, interest, closing balance.

Show table

Year	Opening	Net flows	Interest	Closing

Why Roth

Pay the tax now, keep the growth forever.

A Roth IRA grows every dollar of compound interest tax-free, provided you follow the qualified-withdrawal rules. That means the "future value" tile in this Roth IRA compound interest calculator is the amount you can actually spend — not a pre-tax figure that will shrink when you draw it down. Inflation adjustment is on by default so the number stays honest in today's dollars.

Example · 40 years, 8%, $500/mo

Total contributed$240,000
Tax-free interest~$1.33M
Future value (nominal)~$1.57M
In today's dollars (3% infl.)~$481k

FAQ

Frequently asked

Why does the tax field stay at 0 for a Roth IRA?

Roth IRA contributions are made with after-tax dollars, and qualified withdrawals in retirement are tax-free. There's no annual tax drag on growth, so the tax field should stay at 0 for an accurate projection.

What's the 2026 Roth IRA contribution limit?

For 2026 the limit is $7,500 — $625 a month — plus a $1,100 catch-up if you're 50 or older ($8,600 total, about $717 a month). The limit is shared across all your traditional and Roth IRAs, and higher earners face income phase-outs, so confirm your eligibility on irs.gov.

How does a Roth IRA differ from a 401(k) in this calculator?

The growth math is identical. The tax treatment differs: Roth is tax-free on withdrawal, so leave tax at 0 throughout. A traditional 401(k) is tax-deferred — you still leave tax at 0 during accumulation, then model it at distribution.

Can I include my employer match in a Roth IRA?

No — employer matches apply to employer-sponsored plans like 401(k)s, not individual Roth IRAs. Use the 401(k) calculator for match scenarios.

Is $500/month enough for retirement?

At 8% compounded monthly for 40 years, $500/month grows to about $1.75M — roughly $535,000 in today's dollars at 3% inflation. Only $240,000 of that is your own money; the rest is tax-free growth. Under the 4% rule, $535,000 supports about $21,000 a year in today's money. Whether that's enough depends on your spending, so run your own numbers above.

Tax-free, forty years, one chart.

Change your monthly contribution and watch the real-dollars retirement number update.

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