You do not need to read anything first. Open the app and you'll see a full example already filled in for a person named Alex, age 30. Change any field and the chart updates immediately.

Two ways to begin:

• Start from the example. Edit Alex's numbers to match yours, one field at a time. This is the fastest way to get a feel for how everything connects.
• Start fresh. Clear it out and enter your own life from scratch.

Either way, there's nothing to save or submit. The projection recalculates as you type.

Configure the baseline rules in the Assumptions card:

• Current age and Retire at (the age you plan to stop working)
• Default return (average annual growth of your investments, entered as a nominal rate before inflation)
• Inflation rate
• Life expectancy (how far out the projection runs)
• Withdrawal rate (how much you pull from savings each year in retirement)
• Tax rate (a flat effective rate applied to income; the paycheck calculator helps find your current rate)
• Leftover income (what happens to spare money each month: save to cash, invest in brokerage, split 50/50, pay down debt or mortgage, or spend)
• Retire in (optional; scale living costs to a specific city or state cost of living)
• Lean FIRE spend & Barista FIRE Yearly Income (optional settings to activate Lean FIRE and Barista FIRE milestones)

Fill in as much or as little as you want. More detail means a truer picture.

• Assets. Add each account with its current balance and monthly contribution. You can set a per-account growth override if one account should grow at a different rate than your default, and an age for contributions to stop (defaults to your retirement age). The override is a nominal rate, the same basis as Default return. Account type also decides how retirement withdrawals are taxed: Roth, HSA, and Cash/Savings come out tax-free; Traditional IRA, 401(k), and Pension are taxed in full at your Tax rate; and Brokerage is taxed only on its gains, not the full withdrawal. Contributing to a Traditional IRA, 401(k), HSA, or Pension also reduces your taxable income for that year, up to whatever you earn. An HSA is the only account that is tax-free both going in and coming out. We model that, but not contribution limits or medical-expense rules. See what those medical costs actually look like on the healthcare page.
• Liabilities. Add each debt with its balance and interest rate. For amortizing loans like a mortgage, auto, or student loan, set years left so the balance pays down over time (the table calculates your estimated monthly payment for you). Credit cards and revolving debt model minimum payments without fixed terms.
• Income. Add each income stream with its annual amount. Set a growth rate (or CPI inflation indexing for Social Security), a start age, and an end age for when it stops. For Social Security, enter your estimated annual benefit from your ssa.gov statement at the age you plan to claim it. This calculator does not estimate the benefit for you, and it taxes Social Security on 85% of the benefit rather than 100%.
• Living expenses. Enter monthly spending now (annual totals compute automatically). Optionally set a separate in-retirement amount, toggle whether each expense inflates with cost of living, and set start or end ages to model temporary costs like childcare or college.
• Life events. Add one-time or recurring events like a home purchase, an inheritance, tuition, or a wedding. For cash windfalls, toggle whether the amount is taxable or tax-free.

The chart is the main view. Assets stack up above the line. Debt sits below it. The gap between them is your net worth over time. Reference lines mark your planned retirement age and when you reach FIRE.

Around the chart:

• Summary numbers give you key figures at a glance, and a sticky bar keeps them visible while you scroll.
• Toggle between "Today's money" (purchasing power) and "Future dollars" in the toolbar.
• Click any year (or the sparkline) to open the detail pane for that year and see its full breakdown.
• FIRE milestones track FIRE and Coast FIRE. Enter Lean FIRE spend or Barista FIRE income in Assumptions to track Lean and Barista milestones.
• The Explore section lets you test pre-built stress scenarios side-by-side or run Monte Carlo simulations to test sequence-of-returns risk.

If the projection detects a cash shortage or negative cash flow, warning banners highlight when savings run short.

Directly above the assumptions editor, the Dual-Engine Feasibility Gauge gives you two checks side by side:

• Exit Readiness Score (0 to 100). Measures whether your balance sheet can structurally support your planned retirement age today. It evaluates 5 weighted pillars: safe withdrawal rate coverage (30%), pre-59.5 bridge runway (25%), savings velocity (20%), debt drag (15%), and cash cushion (10%).
• Market Survivability (Monte Carlo). Simulates hundreds of randomized market return sequences to verify if your portfolio survives sequence of returns risk through your life expectancy.

Both matter. A plan can show high market survival in Monte Carlo but fail on feasibility if your money is locked inside a 401(k) and you retire early without a bridge account. The Bottom Line synthesis at the bottom of the gauge highlights your primary constraint.

Open the 5-pillar breakdown inside the Exit Readiness Score card to see which factor pulls your score down:

• Bridge gap. If you retire before 59.5 and your score is low here, you have too much money locked in qualified retirement accounts. Direct future savings into a taxable brokerage account or Roth contributions.
• High withdrawal rate. If your withdrawal rate exceeds 4%, your nest egg target is too small for your spending. Lower your retirement expenses or delay your exit year.
• Debt drag. High fixed debt payments eat into portfolio longevity. Pay down high-interest liabilities or ensure loans amortize before retirement.
• Cash cushion. Aim for 6 to 12 months of living expenses in liquid cash to absorb unexpected market shocks without selling depressed assets.

Everything lives in your browser. There's no account and nothing is uploaded.

• Use Export to download your plan as a file.
• Use Import to load that file back later, or to move your plan to another device.

If you clear your browser data without exporting first, your plan is gone. Export if you want to keep it.

Enter your home’s full market value as a Real Estate asset, and add the mortgage separately under Liabilities (with a term, so it pays down). Net worth is assets minus debts, so your equity (value minus what you still owe) grows on its own from both appreciation and each mortgage payment. Do not enter your equity as the asset while also carrying the mortgage; that subtracts the loan twice.

Real estate is treated as illiquid: it counts toward your net worth but is never sold to fund retirement, so your withdrawals draw only from cash and investment accounts. Property tax, insurance, and upkeep have no separate field. Add them as Housing living expenses (you can set a different in-retirement amount).

• You can’t delete or reclassify your last cash or savings account. The engine always needs one place to hold money.
• For a mortgage or car loan, set the years remaining. Without it, the loan will not pay down and it will drag on your net worth forever.
• In-retirement expenses are entered in your current city’s prices. If you set a retirement city, its cost-of-living multiplier is applied on top. Enter today’s prices and let the multiplier do the adjusting. Do not adjust them yourself, or you’ll count it twice. The multipliers are measured against a US average, not against your city, so if you already live somewhere unusually cheap or pricey, set the retirement amounts to match what you expect to spend.