US Tax Tools

Backdoor Roth IRA Calculator

High income over the Roth IRA limit? The backdoor Roth strategy lets you contribute anyway — but the IRS pro-rata rule can trigger unexpected taxes if you have other traditional IRA funds. Use this calculator to estimate your conversion tax and project your tax-free Roth growth over time.

Conversion Tax Calculator

Estimate how much tax you'll owe on your backdoor Roth conversion using the IRS pro-rata rule.

Inputs

Sum of all pre-tax (deductible) IRA balances across all accounts

2025 IRA contribution limit: $7,000 ($8,000 if age 50+)

Any earnings between contribution and conversion date

Your highest federal income tax bracket

Converting $7,000 to a Roth IRA, you'll owe $0 in tax (0.00% effective rate). $7,000 of the conversion is tax-free.
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Tax-Free Amount

$7,000

Tax Owed on Conversion

$0

Effective Tax Rate

0.00%
Pro-Rata Breakdown
Total IRA Balance$7,000
After-Tax %100.00%
Taxable Amount$0
Tax-Free Amount$7,000
Tax Owed$0

Roth Growth Projector

Project the tax-free growth of your Roth IRA over time with annual contributions.

Projection Inputs

Starting balance after your first conversion

Amount added each year via backdoor conversion

Historical stock market average ≈ 7% real return

Number of years to project growth (1–50)

Projected Value

$714,511

Total Contributions

$217,000

Tax-Free Growth

$497,511
Year-by-Year Projection
YearBalance
1$14,490
2$22,504
3$31,080
4$40,255
5$50,073
6$60,578
7$71,819
8$83,846
9$96,715
10$110,485
11$125,219
12$140,985
13$157,853
14$175,903
15$195,216
16$215,882
17$237,993
18$261,653
19$286,968
20$314,056
21$343,040
22$374,053
23$407,237
24$442,743
25$480,735
26$521,387
27$564,884
28$611,426
29$661,226
30$714,511

Frequently asked questions

What is a backdoor Roth IRA?

A backdoor Roth IRA is a two-step strategy that lets high-income earners contribute to a Roth IRA even if they exceed the direct contribution income limits ($165,000 single / $246,000 MFJ for 2025). You first make a non-deductible contribution to a traditional IRA (no income limit), then convert those funds to a Roth IRA. While the conversion may trigger some tax if you have other pre-tax IRA funds (due to the pro-rata rule), the money then grows tax-free forever.

What is the pro-rata rule and how does it affect my backdoor Roth?

The IRS pro-rata rule (IRC §408(d)(2)) requires that all your traditional, SEP, and SIMPLE IRA balances be treated as a single pool when calculating the taxable portion of any conversion. If you have $93,000 in pre-tax IRA funds and contribute $7,000 non-deductible, only 7% of your conversion is tax-free — the other 93% is taxable income. To avoid the pro-rata rule, consider rolling your pre-tax IRA funds into your employer's 401(k) plan before doing the backdoor conversion.

Who should use the backdoor Roth IRA strategy?

The backdoor Roth is most beneficial for high-income earners who exceed the direct Roth IRA income limits, expect to be in a similar or higher tax bracket in retirement, and have no (or minimal) existing pre-tax IRA balances — or can roll pre-tax funds into a 401(k) to sidestep the pro-rata rule. It is especially powerful for younger investors with many years for tax-free growth to compound.

What are the 2025 income limits for a direct Roth IRA contribution?

For 2025, the ability to contribute directly to a Roth IRA phases out at $150,000–$165,000 for single filers and at $236,000–$246,000 for married filing jointly. Above these limits, direct contributions are not allowed — but the backdoor strategy has no income limit. The annual IRA contribution limit is $7,000 ($8,000 if you are age 50 or older).

Sources

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Last updated April 22, 2026 Tax year 2025-26

Data sources: IRS (irs.gov), Social Security Administration

This tool is general information only, not financial advice.

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