Net Worth Forecast Calculator — Year-by-Year Projection

It steps through your life one calendar year at a time, starting in 2026 (the balances you enter are treated as the start of 2026, so the first row is a full year). Each year it works out your pay, your 401(k), Roth IRA and HSA contributions, the taxes on your income, your spending and loan payments, and any one-off costs or windfalls. What is left over goes into savings or investments (or, if you spend more than you earn, comes out of them). Then every account grows at the return you chose. New money is assumed to move in evenly through the year, so it earns half a year of return in the year it is added.

Each year's change in net worth is the money coming in, minus taxes, spending and loan interest, plus what the investments and the home earned. Our automated tests check that identity in every year of hundreds of randomly generated scenarios.

The first is in the dollars of the year itself: a million dollars in 2066 buys much less than a million dollars does today. The second divides by your inflation assumption to show the same amount in today's (2026) dollars, which is the one that is easier to compare with what you own now. Your spending, one-off costs, Social Security and the tax brackets are all entered or grown in today's dollars, so an inflation figure that is too low makes the future look better than it will be.

Federal income tax uses the 2026 brackets and standard deduction (IRS Rev. Proc. 2025-32) with the standard deduction for age 65 and over. Because the law adjusts brackets and the standard deduction for inflation every year, the forecast assumes they grow with your inflation figure. Social Security and Medicare tax use the statutory rates, the 2026 Social Security wage base ($184,500, projected to grow with inflation) and the 0.9% Additional Medicare Tax. State income tax uses this site's state tables on wages and retirement withdrawals.

Some amounts are deliberately not grown, because the law does not adjust them: the Additional Medicare Tax thresholds ($200,000 single, $250,000 joint) and the income levels at which Social Security benefits become taxable ($25,000 and $34,000 single, $32,000 and $44,000 joint). So with inflation, more of a retiree's benefits become taxable over time, which is how the rules work. The extra deduction for people 65 and over introduced in 2025 is included only through 2028, the years the law provides it.

Example, first year: a single filer in Texas earning $100,000 who puts 10% into a traditional 401(k) has taxable income of $73,900 ($100,000 less $10,000 less the $16,100 standard deduction), federal income tax of $10,970 and Social Security and Medicare tax of $7,650 (the 401(k) reduces income tax but not those). That matches this site's Paycheck Calculator.

The 2026 figures from IRS Notice 2025-67 and Rev. Proc. 2025-19: $24,500 of employee 401(k) deferrals; a catch-up of $8,000 from age 50, or $11,250 at ages 60 to 63; $72,000 for employee plus employer contributions in total; $7,500 for an IRA plus $1,100 from age 50; and an HSA limit of $4,400 (self-only) or $8,750 (family) plus $1,000 from age 55. Your percentage applies to pay up to the plan compensation limit ($360,000). The employer match is your contribution times the match rate, on the first part of pay you set.

In later years the limits are grown with your inflation assumption using the rounding rules in the law (for example, the 401(k) limit moves in $500 steps, and the age 60 to 63 catch-up stays put until inflation has added at least $500 to it). The IRS announces the real limit each autumn, so a future year here is an estimate.

Roth rules: a Roth IRA contribution is cut down when income is in the phase-out range ($153,000 to $168,000 for a single filer in 2026, $242,000 to $252,000 for a married couple filing jointly), by the method in IRS Publication 590-A. And if you are 50 or over and your pay last year was over $150,000, the catch-up part of your 401(k) deferral has to go in as Roth (26 U.S.C. § 414(v)(7)); the calculator assumes your plan offers a Roth option.

Pay and new contributions stop, spending changes to the percentage you choose, and Social Security starts at the age you set. Spending is met from cash first, then taxable investments, then pre-tax accounts, then Roth accounts. Each pre-tax withdrawal is grossed up so the amount left after income tax covers the spending; before age 60 (a simplification of 59½) the 10% additional tax on early withdrawals is added if you leave that box ticked (IRS Topic 558 lists exceptions the calculator does not model). Required minimum distributions start at 73 for anyone born from 1951 to 1959 and at 75 for anyone born in 1960 or later, using the Uniform Lifetime Table, and are taken even if you do not need the money. If everything runs out, the shortfall is treated as borrowing, and the summary shows the age it happens.

See the RMD Calculator and the Taxable Social Security Calculator for the rules that drive those two pieces on their own.

There is no correct number, and the forecast will not follow any straight line. The defaults (7% investment return, 2.5% inflation, 3% raises) are placeholders you should replace. The box under the chart shows the same plan with the investment return two points lower and higher so you can see how much of the answer depends on that one guess. A forecast is more useful for comparing choices (retiring at 62 or 67, saving 10% or 15%, buying or renting) than for predicting a number.

Capital gains tax when you sell taxable investments (use the yearly tax-cost input, a rough stand-in for dividends and gains); the 3.8% net investment income tax, credits, itemized deductions and the alternative minimum tax; the way each state treats retirement income and Social Security; health insurance, Medicare premiums and long-term care; selling or downsizing a home; a partner's own 401(k) (a spouse's pay is taxed and stops when yours does, and the spouse is assumed to be your age); Roth conversions; and 457(b), SIMPLE, and after-tax plan contributions.

It also treats Roth withdrawals as tax-free at any age, never draws on the HSA, does not take retirement accounts down while you are still working, and ignores the delay to April 1 that the law allows for the very first required distribution. These simplifications are chosen to keep the forecast readable; they are not recommendations.

No. The forecast runs in your browser and nothing you type is stored or sent. The site records only that the calculator was used, with no figures, so it can see which tools are useful.