Model your whole financial life, year by year.

Enter your income, spending, accounts and debts. Add the house, the kid, the year off. See when you could retire, whether the money lasts, and what each decision changes in every year after, US taxes included.

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firemodeling.com / plans / early-retirement
Demo: try a what-if
Net worth at 31
$158k
Net worth at 85
$2.88M
FIRE reached
Age 52
Money lasts
Through the model
$1M$2M$3M$4M354555657585COASTFIREFIRE
Net worthCash savingsTaxableTax-deferredTax-freeHome equity
Hover or tap any year to drill in
Year detailAge 52 · 2047
Net worth$1.57M
+105k vs prior year
Liquid Net Worth$906k
Withdrawals$0k
Withdrawal Rate0.0%
Income$95k
Taxable Income$84k
Taxes$10k
Effective Tax Rate11.8%
Spending$62k
Expenses$62k
Savings Rate34.7%
Tax Balance$0k
Portfolio allocations
Tax-free$167k · 11%
Tax-deferred$497k · 32%
Taxable$858k · 55%
Cash savings$48k · 3%
Milestones
CoastFIREage 36
FIREage 52
Retirementage 52
A simplified demo in today’s dollars. FIRE here means savings of 25× yearly spending. Your own model runs the full simulation, taxes included.
What goes in

Model the details a simple calculator rounds off.

A basic retirement calculator takes a balance, a savings rate and a return, and draws one curve. A spreadsheet goes further, until every year needs a tax estimate and one moved date means re-dating rows. Here each income and expense has its own start, end and way of changing, for one person or a couple.

Income that changes

Salary, hourly work, side income, RSU income, a pension, Social Security, an inheritance. Go part-time at 55 or take a year off at 33: set pay to any share of normal, down to zero, for the years you choose.

Spending that changes

Rent, a dependent, education, travel, a wedding. Each follows inflation, outpaces it or stays flat, and is marked essential or discretionary, which is what a flexible-spending strategy trims. Health care can be a marketplace plan with an estimated subsidy; Medicare is added at 65.

The house, start to finish

Buy at 35 with a down payment, a rate and a monthly payment. Each year carries property tax, maintenance and appreciation. Sell at retirement and the broker’s fee, capital-gains tax and home-sale exclusion are worked out. Rental property and cars are covered too.

Debts with an end

Student loans and other debts each have a balance, a rate and a monthly payment. Send spare cash at one to clear it sooner. Student loans can carry a forgiveness date, and a Debt Free milestone marks the year you are clear.

Accounts by tax type

Every account counts as cash, taxable (brokerage), tax-deferred (401(k), IRA) or tax-free (Roth, HSA, 529). The type decides what a withdrawal costs, including the 10% penalty on retirement money before 59½. Set a stock and bond mix that shifts as you age.

Surplus and shortfall

A good year’s spare money follows your list, in order: top up cash, fund the 401(k) and the Roth, pay down a debt, invest the rest. A short year draws on cash, taxable, tax-deferred and tax-free money in the order you set.

Milestones

Set the rule. The model finds the year.

A milestone is a life event with a rule, and it happens the first year the rule is true. Other things hang on it: salary ends at Retirement, the house sells at Retirement, tuition starts at Start School. Retirement itself can happen at FIRE, so salary ends the year the rule is met.

FIREage 52 in this model. A result, not an input.
whenNet Worth 25 × Spending
andTotal Debt $0
orAt Age 55

Conditions can be an age, a date, a financial measure like net worth or total debt, or another milestone. “Two years after the year off” works too.

  • FIRE stands for financial independence, retire early. LeanFIRE, FatFIRE and CoastFIRE milestones are built in
  • Retire three years earlier: move one milestone, and everything tied to it moves too
  • A kid, a move, a new job: add the milestone, then attach the costs and income it brings
  • If spending ever goes unfunded, a “Money runs out” marker shows the year
What-if

Ask “what if?” Keep both answers.

Every edit re-runs the whole model in your browser, and nothing is saved until you choose to. To keep two versions of a life, clone the model and change the copy. Compare draws the other model as a dashed line on the net-worth chart, and Year detail shows the difference under each headline figure.

What if my spending drops later in retirement?
Give an expense different growth rates at different ages, or end one budget and start a smaller one.
What if the coming decades repeated 1966, or 2000?
Replay actual US stock returns, bond returns and inflation from a start year you choose. The data runs 1928–2024. One stretch of history per run.
Claim Social Security at 62, 67 or 70?
Enter your benefit and pick a claiming age. If you expect it to pay less, set the share you think you’ll receive.
Same life, in a state with no income tax?
Clone the model, change the state and compare. Income tax for all 50 states and DC is built in.
Enter your own numbers

You type in a birth date, your state and your balances. A step-by-step wizard then takes you through milestones, income, expenses and assets, and saves your place.

Year by year

Read any single year. Then test the whole model.

Slide to any age and Year detail shows that year’s net worth, income, taxes, spending, withdrawals and savings rate, in Today’s $ (inflation taken out) or Future $. Tax Analytics lists that year’s estimated tax return line by line. Chart it with 36 built-in plots or build your own, and download the yearly table as CSV or JSON.

Cash flow for any year
One simulated year, as a flow diagram
Income$158k
Taxes$38k
Spending$62k
Saved$58k

Paychecks and withdrawals come in on one side. Taxes, expenses, debt payments, purchases and contributions go out the other, ending in the accounts your savings land in.

Taxes, every year
Taxes by type in one simulated year
Federal
State
FICA
Gains

Each year gets an estimated US tax return: federal brackets, your state, payroll taxes (FICA), capital gains, standard or itemized deductions, Social Security taxation, required retirement withdrawals. Over- or underpayment settles the next year as a refund or a bill. For planning, not filing.

0%
Chance of Success
Monte Carlo, up to 10,000 trials

Each trial re-runs your whole model, taxes and milestones included. Returns and inflation are sampled from 1928–2024 US history, each year’s figures kept together, or from an average and spread you set. See how often the money lasts, and whether failures come early or late.

Strategies

Test a tax or withdrawal strategy without editing your model.

A strategy is a retirement choice: which accounts to spend first, when to move money into a Roth, how much to trim after a bad year. Switch one on and the app runs the model both ways, showing the change in lifetime taxes, net legacy (what heirs would receive) and, when you ask, chance of success. It reports; you decide.

Example figures · one strategy on at a time
Roth conversions to the 22% bracket
+$184k net legacy
Harvest gains while taxed at 0%
−$61k lifetime taxes
Spend tax-deferred before taxable
+$27k lifetime taxes
The 4% rule instead of your budget
−$112k net legacy
Trim discretionary 30% after a bad year
+6 pts success
Assumptions

What it assumes, and what it leaves out.

Beyond your own numbers and the built-in US tax rules, results come from three things you control: the rates you assume, the events on your timeline and the strategies you layer on top. The projection has no randomness: when a number changes, you changed something. These rates are defaults, before inflation; change any, or set them by age.

Stocks
7%
5.5% growth + 1.5% dividends
Bonds
5%
1.5% growth + 3.5% interest
Inflation
3%
takes Future $ back to Today’s $, and indexes tax brackets
Cash savings
4%
yield on savings
Estimates, in yearly steps
Illustrative estimates of where your own choices lead, one year per step. Not advice, not a prediction, not a monthly budget.
US only
Dollars, US federal and state tax only. Each model uses one state throughout; filing status is single or married filing jointly.
Nothing is linked
No bank connections, no ad trackers, no data selling. You type balances in; update them once and every model built on today’s finances re-projects.
Free to build, Premium to open
Net-worth tracking, building models and a net-worth preview of each are free. Opening a model’s full results is $89 a year: 3-day free trial, card required, cancel anytime.

Start with today’s numbers. Model every year after.

FIREModeling — personal finance projection