Using the Fire Planner

Why Track Your FIRE Progress

Financial independence isn't a single moment. It's a gradual shift. Tracking makes that shift visible. It turns "I want to be financially independent" into a date, "Retiring Oct 2042, at 48", and into a check-in that says you are $4,200 ahead of plan.

Regular tracking makes goals concrete, reinforces saving habits, prevents lifestyle inflation from eating your progress, and catches problems (like debt growing faster than payments) before they become expensive. You don't need to obsess over daily market movements. But ignoring your finances entirely means you won't notice problems until they're hard to fix.

Setting Up Your Plan

The Fire Planner builds a complete picture of your finances: income, spending, accounts, debts, and one-time events. Everything lives in your browser. Nothing is sent to any server.

The Quick-Start

A first visit opens with five questions: your age, invested savings, monthly spending, monthly income, and when you want to retire (as early as possible, or in a year you pick). See my plan makes the plan and shows the answer. The plan starts with three lines that hold your totals: a salary, a spending line, and an investment account. A three-step tour follows the first time.

Coming from a calculator? Its Continue in the Fire Planner with these numbers link opens the quick-start with what the calculator knows filled in. The plan it makes sits beside any plans you already have.

You: Birth Date, Retirement Date, and Horizon

The inputs column starts with You, three rows:

• Born: the month and year. Every age in the plan comes from it, including the 59.5 rule's.
• Retire: "suggested" is the earliest month your money lasts, found again whenever the plan changes. "your choice" holds a month you pick instead.
• Money must last until: age 90 by default. The plan runs to the end of that year, and a date only works if the money lasts that long.

Your retirement date is when the engine switches from saving (contributions in, surplus deposited) to drawing down (accounts pay for your spending). Income set to end "at retirement" stops on this date.

Adding Accounts

Add each investment account, savings account, or property in the Assets section. There are 9 types, each with its own default growth rate:

Each account's form has a Growth choice: market rate or custom. Market rate follows the Average return in Assumptions (7% by default), and it is the rate Monte Carlo and the backtest replace with their own returns. Custom keeps a rate of your own.

A new account starts with its type's growth from the table. Retirement accounts, Roth, HSA and taxable brokerage follow the market rate. High-yield savings, real estate equity, cash, crypto and Other start at a custom rate of their own. Pick the type first: the growth follows it until you save the account.

You can also set a monthly contribution for each account. Untick Count this in the plan to keep an account in the list without counting it.

Adding Liabilities

Add debts with a balance, interest rate, and monthly payment. The engine accrues interest monthly, then applies your payment. If your payment doesn't cover the monthly interest, the planner shows a warning, because that debt will grow forever.

Each debt's row shows the month it is paid off, based on your payment.

Adding Income

Income lines are money coming in. Each has a type, an amount per month or per year, when it starts and ends, and a yearly growth rate:

Set Ends to at retirement for income that stops when you retire (like salary). Set Starts to a date for income that starts later (like Social Security at 67). Under the income lines, Unspent income says where money left after spending, contributions, and debt payments goes: into an account, or not invested.

Adding Expenses

Expenses grow with inflation. Each category adds its own offset to the plan's inflation, because healthcare costs rise faster than groceries. At the default 3% inflation:

Change Inflation in Assumptions and every line that grows with inflation follows it. Untick that box to give a line a rate of its own. Like income, expenses can be monthly or yearly and can start and end on a date.

One-Time Events

One-time events model windfalls or large expenses in a month you pick. Set Direction to Money in for an inheritance, a bonus, or a home sale, and to Money out for a wedding, a home purchase, or a medical bill.

Money in goes to, and money out comes from, wherever your surplus goes. You can name an account instead. Money out that this account cannot cover comes out of your other accounts, in the order withdrawals take them. Events are applied during the projection in the month they occur, and the Money flow shows each one in its year.

Totals That Split

The quick-start's three lines hold the totals you typed. While they do, Income and Expenses say "Your total stays … Lines you add split it." Assets says "… Invested accounts you add split it." An income line you add comes out of the quick-start's salary, an expense out of its spending line, and an investment account out of its savings. Your totals stay what you said until you change them.

Each form says what saving it does before you save: "Your total stays …", "Your total grows to …", or "This adds to your total." Cash, a high-yield savings account, and a home's equity add to your total, because the quick-start asked for invested savings. Lines that start later add too.

Assumptions

The Assumptions section holds the rest:

• Average return: 7% a year before inflation, the market rate for your accounts.
• Inflation: 3% a year. It turns future money into today's money and sets the rate of every expense line without its own.
• Withdrawal order and the early withdrawal penalty: see withdrawal strategies.
• Monte Carlo: 500 simulations by default (100 to 5,000), with 15% yearly swings (1 to 40%).
• Historical backtest: how many start years fit the market history, and how long each one is. Your plan's length sets both.

Reading the Answer

The answer starts with one line: "Retiring Oct 2042, at 48". With "suggested", it is the earliest month your money lasts to your "Money must last until" age. With "your choice", it is your date. Everything under it grades that date. For the exact math, see How Projections Work.

Three Models

Three cards grade the date side by side:

• Average returns: your plan at steady growth. It says "money lasts to age 90" or the year the money runs out.
• Monte Carlo: your plan through 500 random markets. It counts the runs where the money lasts: "money lasts in 462 of 500 simulations".
• Historical backtest: your plan through every start year since 1872. It counts the start years where the money lasts: "money lasts in 82 of 96 start years".

Each card also shows your net worth at retirement (the median for the two simulations): what you have as you retire, at the end of the month before your retirement month. Every "at retirement" figure reads that month. The ? on a card explains it in a few sentences. Pick a card and the lines, the chart, and "What moves it" under it follow that model. Average returns says how much money is left at age 90. With a date of your choice, it also says how much you could spend each month and still have money to age 90. Monte Carlo and the backtest say how their best and worst 10% end.

The simulations run by themselves, a moment after each change. A card still counting is dimmed until its new count lands. The same plan always gets the same count, on every device, and a change that moves no money (a line split in two, a name) moves no count.

Today's Money or Future Money

The switch under the headline shows every sum in today's money (what it buys now) or future money (the number your statement will show then). Monthly amounts are always in today's prices.

What Moves It

Three rows show what one change does to the model you picked: spend 10% less, retire 3 years later, or earn and save 500 a month more. With a suggested date, the spending and saving rows also say how much earlier you could retire. Each row opens the section you would change. Under them, every input is one click away.

Could You Stop Saving Today?

The coast question: if every contribution stopped today and you still retired on your date, would the money last? With a suggested date, it also says where that date would move without more saving. For the idea behind it, see Coast FIRE.

When There Is No Date

With no spending or no birth date, the headline asks for it. When no date before your "Money must last until" age works, it says so and links to Income, Expenses, and You. If your savings run out while you are still working, it names the year. Already retired? It says "Retired" with the month, and the cards grade your plan from today.

The Evidence

Under the model's lines, four tabs show why the answer is what it is: Path, Money flow, Saved vs growth, and Table. The Full screen button opens a chart in a larger view.

Path

Your net worth at the end of each year, for the model you picked. Average returns is one line. Monte Carlo shows the middle 50% and 80% of simulations around the median. The backtest adds its worst start year (dashed) and its best (dotted). A dotted line marks your retirement. The line above the chart says when your net worth peaks, or the year your savings run out.

Survival by Start Year

On the backtest, a table headed "Survival by start year" sits under the Path. It's a Trinity Study-style grid: withdrawal rates from 3.0% to 6.0% (rows) against all years and each decade (columns). Each cell prints the share of start years where the money lasted. Stronger gold means more lasted, and red means fewer than half did.

It is not your plan. It tests a 100% stock portfolio (S&P 500 with dividends) that withdraws a fixed share of its starting value, raised each year with actual inflation (CPI), not your plan's rate, over your retirement length (retirement date to end year). It shows rates only, never amounts from your savings. Its start years are its own: a test as long as your retirement fits a different number of them than the backtest, which runs your whole plan from today. It ignores your income, spending, accounts and stress tests. The backtest above covers those. Use it for a quick answer to "how safe is my withdrawal rate?" across 150+ years of market data.

Money Flow (Sankey)

The Money flow tab shows where one year's money goes on the average path. Pick any full year (the first year is a part year, so the picker starts at the next one), and switch between the year's sums and its average month.

While you work, income pays for spending, debt payments and savings, and the savings go on into each account. In retirement, the accounts you draw on (and any pension) pay for spending. Money taken from one account to fund another's contribution only moves between accounts, so it does not show as income.

If your savings run dry, "Not covered" is the part nothing pays for. Unspent income you chose not to invest shows as "Not invested". The same flows are listed in words under the chart.

Saved vs Growth

The Saved vs growth tab stacks two areas from now to your retirement date:

• Money you put in: what you hold today, plus contributions, invested unspent income and one-time events, less what you take out
• Market growth: the rest of what your accounts hold by then

The line above it reads like "By Oct 2042 you put in $420k and growth adds $680k." In today's money, growth is what your accounts gained above inflation.

Year-by-Year Table

The Table tab lists your plan year by year, in today's or future money as the money switch says: the first and last years, every 5th year and your retirement year, or every year with "Show every year".

• Net worth (end of year): on Monte Carlo and the backtest, their median
• Income, Spending and Withdrawals: the year's sums on the average path. A one-time event counts in its year: money in with Income, money out with Spending, its name under the year. ⚠ marks a year whose withdrawals include money from a retirement account while the early withdrawal penalty applies.

The plan starts this month, so the first year is a part year, and the table says so.

Stress Testing Your Plan

A plan that only works in perfect conditions isn't a plan. Stress test this plan, under the evidence, lists six tests. Tick one and its numbers appear under its name, ready to change. The answer, every model, and the evidence include the tests you have on. The line under the headline names them, with Turn off. You can turn on as many as you want. For the exact formulas, see stress test calculations.

Market Crash

Question it answers: What if the market drops 30% in 2 years?

Simulates an immediate percentage drop in risky assets (stocks, real estate, crypto) at a specified year (0-50), followed by slower growth that fades back to normal over 1-50 years. The drop itself is never made back. Drop severity ranges from 1-95%. Cash and savings accounts are protected. Defaults: 30% drop in year 2, 5 years of slower growth.

Lower Returns

Question it answers: What if the next few decades underperform historical averages?

Permanently subtracts a percentage (0-15%) from every asset's growth rate and the global default rate. A 2% reduction turns 7% growth into 5%. Default: reduce by 2%.

Income Loss

Question it answers: What if I lose all income in 3 years?

Zeroes out all income streams starting at the specified year (0-50). Permanently. This is a worst-case scenario for job loss without replacement. Default: income stops in year 3.

Spending Spike

Question it answers: What if my spending jumps 50%?

Multiplies all expenses by a percentage increase (1-500%) starting at the specified year (0-50). Permanent from that point forward. Useful for modeling a health crisis, new dependents, or relocation. Defaults: +50% in year 2.

High Inflation

Question it answers: What if inflation spikes to 6% for 3 years?

Overrides the default inflation rate (1-30%) for a time-limited window (1-20 years), starting 0-30 years out. After the duration, inflation returns to your base rate. Prices keep the level they reached, so your spending never falls back. Defaults: 6% inflation starting immediately, lasting 3 years.

Retire Earlier or Later

Question it answers: What if I have to stop work two years early?

Moves your retirement date by whole years, from 20 years earlier to 30 years later. Default: two years earlier. A suggested date moves after it is found, and so do the dates under "What moves it" and the coast question. It never moves a date that is still ahead to before this month. Income that starts on your retirement date, like part-time work or a pension, moves with it.

Withdrawal Strategies

Once you pass your retirement date, the engine needs to decide which accounts to pull from. Withdrawal order in Assumptions sets it. For the exact calculations, see retirement withdrawal calculations.

Taxable First (Default)

Depletes accounts in a tax-aware order, one at a time:

1. Taxable accounts (brokerage, high-yield savings, cash)
2. Retirement accounts (401k, IRA) and HSA
3. Roth accounts (Roth IRA, Roth 401k)
4. Everything else (real estate equity, crypto, other)

The idea: spend taxable money first, let tax-advantaged accounts compound as long as possible, and save Roth (tax-free) for last.

Proportional

Withdraws from all eligible accounts simultaneously, proportional to their balance. If your brokerage holds 60% of your total and your 401k holds 40%, withdrawals are split 60/40. This keeps your asset allocation roughly constant through retirement.

Custom Order

Pick Custom order and your accounts appear in a list. Move each one up or down with its ↑ and ↓ buttons. The engine drains them in that order, one at a time. An account you add later joins the end of the list. Use this if you have a specific strategy (e.g., drain a particular account first for tax bracket management).

The 59.5 Rule

Off by default. Tick Early withdrawal penalty in Assumptions (before age 59.5, which you can change) and the engine skips retirement accounts (401k, IRA, Roth, HSA) while you're younger than that. It withdraws only from non-retirement accounts first. If those run dry and you still need money, it pulls from retirement accounts anyway and marks those years with ⚠ in the Table, a warning that real-world penalties would apply. The penalty itself is not counted.

This matters most for early retirees. If you're retiring at 45, you need enough in taxable accounts to bridge the gap until 59.5.

Tracking Over Time

Check-Ins

A check-in records your real balances on a date. In the Check-ins section, + Record a check-in opens its form: the month and year (this month at first) and a new balance for each account you count and each debt. Leave a field empty to skip it. The newest check-in sets those balances in your plan. One you record for an earlier month only adds to your history. There is one check-in a month: record again in a month that has one and that check-in takes the new balances. The form says so before you save.

Each check-in is one row: its month, your net worth, and the change since the one before. Open a row to edit or delete it. Deleting a check-in keeps the balances it set.

Recommended frequency: Monthly, on the same day. Consistent timing makes trends visible. Quarterly works if you prefer less maintenance. Add a calendar reminder (.ics) under the section puts a monthly check-in in your calendar.

Prefer to keep your own record? The FIRE tracker spreadsheet does the same monthly log in Excel or Google Sheets: net worth, contributions vs growth, and milestone dates, with no account required.

Ahead or Behind Plan

The planner keeps your plan as you first set it up (it follows your edits for the rest of that day, or until your first check-in, then stays fixed). The newest check-in's row says how far ahead of or behind that plan you are ("$4.2k ahead of plan"), or "on plan". A check-in on the day you set the plan up stands against it as you set it up.

Complete Your Plan

Beside the answer (on phones, under it), Complete your plan lists five steps: add your real income lines, split spending into categories, add your accounts, add one life event, and record your first check-in. Each one ticks itself once your plan shows it, and you can tick or untick it by hand. → open takes you to its form.

At 5 of 5, the planner offers three next steps: a calendar reminder to check in each month, the firenum newsletter, and a professional to run your plan by.

Health Warnings

The tracker checks your numbers for likely typos and for money the plan quietly takes from your savings. A warning never blocks anything. It is one line in the section it is about, under the line it concerns, and "why" explains it in one sentence:

Dismiss hides a warning for 7 days. If the problem is still there after that, it comes back. A warning also clears by itself once you fix the number, for example a debt payment raised above the interest.

Plans, Sharing, Export, and Import

Multiple Plans

Keep up to 5 plans in the plan menu, which shows your plan's name in the top bar ("My plan" at first). New plan from these numbers opens the quick-start filled in from the plan on screen and adds the result beside it. Duplicate copies the plan with its check-ins. Rename and Delete… work right in the menu.

Compare plans opens a panel under the top bar, one row per plan: when it retires, whether the money lasts on average returns, its Monte Carlo and historical backtest counts, and net worth at retirement. File ▸ Load a demo plan adds one of three example plans beside yours and opens it. A notice says so. Your own plans stay in the plan menu. Plans live in this browser only, with no account. Open the planner in two tabs and a change in one reloads the other, so neither saves over the other.

Shareable Snapshots

Click Share for a link to the plan you have open, then Copy link. The link holds your numbers: every line with its name and dates, the assumptions, the withdrawal order, the stress tests you have on and the Monte Carlo settings. The plan's name, check-ins and switched-off accounts stay out. Your birth date becomes a year.

Anyone who opens the link sees your plan as a shared plan: they can explore it and change it, but nothing is saved and their own plans are untouched. Save as a new plan keeps it beside their own plans, named "Shared plan". With five plans already, they delete one first.

CSV Export

File ▸ Export plan (CSV) downloads the plan you have open. The file starts with the plan's name, lists your check-ins as rows a spreadsheet reads (date, account or debt, type, previous balance, new balance, change and total after), and ends with a backup of the whole plan.

CSV Import

File ▸ Import plan (CSV)… reads that backup. The planner then asks whether to replace the plan you have open, which keeps its name, or to import it as a new plan beside your others, named as in the file. A file that holds no plan, or one the planner cannot read, is turned down, and nothing changes. Files from older versions of the planner import too.

To restore a backup in a new browser, or after deleting all data, finish the quick-start first. Any numbers will do. Then choose File ▸ Import plan (CSV)… and Replace: the plan from the file takes the place of the one the quick-start made.

Clearing Data

File ▸ Delete all data deletes every plan in this browser: assets, liabilities, income, expenses, events, check-ins and assumptions, along with everything else the planner keeps there. It also deletes the numbers you typed into the calculators, so none of them fill in the quick-start again. Your currency, text size, theme and cookie choice stay. The menu asks first. This cannot be undone. The quick-start opens afterwards, as on a first visit.

Start with the five numbers the quick-start asks for. Add your real accounts, income, and expenses, then stress tests, as you get comfortable. The answer gets more useful the more of your real plan it holds.