Every formula, every number, and where each came from.

Formulas

All rates are real (after inflation), so results stay in today’s dollars. If you think in nominal returns, convert with the Fisher equation below.

Why a range of withdrawal rates

There is no single correct withdrawal rate. Morningstar’s 3.9% for 2026 uses forward-looking return estimates and a 90% success target over 30 years. Bengen’s 4% (1994) and 4.7% (2025) are historical worst cases over 30 years. Early Retirement Now’s 3.25% to 3.5% comes from testing 50 to 60 year retirements, which is the horizon most early retirees face. The method and the horizon explain most of the gap.

Glossary

Every dotted-underlined word on this site, in plain terms. Tap or hover one anywhere to see it in place.

72(t) payments Accounts

Substantially equal periodic payments: a fixed schedule of withdrawals that avoids the early-withdrawal penalty at any age, if you keep it going long enough.

Barista FIRE The idea

Leaving full-time work once your portfolio covers the part of your spending that part-time or other income does not.

Catch-up contribution Accounts

Extra room above the normal contribution limit once you reach a set age, usually 50, or 55 for an HSA.

Coast FIRE The idea

Having enough invested that growth alone would reach your FIRE number by a traditional retirement age, even if you never added another dollar.

COLA Benefits

Cost-of-living adjustment. The yearly raise Social Security applies to keep benefits in line with inflation.

Compounding The math

Growth on top of earlier growth. Each year’s return is earned on a balance that already includes the returns before it.Example: $10,000 a year for 10 years at 5% grows to about $125,779, not $100,000.

Dividend yield Investing

A year of dividends as a share of the price. It is only part of total return, and it changes every day.

Employer match Accounts

Money an employer adds to your workplace retirement plan when you contribute. The plan’s own rules say how much and on what terms.

Fat FIRE The idea

FIRE on a generous budget. Also a community label with no official threshold.

FIRE The idea

Financial Independence, Retire Early. Saving and investing enough that your investments can pay for your life, so work becomes a choice.

FIRE number The math

The portfolio size that can fund your yearly spending at a chosen withdrawal rate. It is your spending divided by that rate.Example: $40,000 a year at 4% is $1,000,000.

Full retirement age Benefits

The age at which Social Security pays your full benefit. It is 67 for anyone born in 1960 or later.

Guardrails Investing

A spending rule that cuts or raises withdrawals when your current withdrawal rate drifts too far from where it started. Flexible spending is why some studies support higher starting rates.

HSA Accounts

Health Savings Account. Paired with a high-deductible health plan, it pays for medical costs, and the IRS sets its limits each spring.

Inflation The math

Prices rising over time, so the same dollar buys less each year.

Lean FIRE The idea

FIRE on a deliberately small budget. A community label with no official threshold.

Median and mean Data

The median is the middle value; the mean is the average. A few large balances pull the mean far above what a typical family has.

Portfolio Investing

Everything you have invested, taken together.

Principal Investing

The money itself, as opposed to the income or growth it produces.

Real return The math

Investment growth after inflation is taken out. Using it keeps every number in today’s dollars, so $40,000 means what $40,000 buys now.Example: 7% growth with 3% inflation is about 3.9% real.

Regional Price Parity Data

A government index comparing price levels between places, where the US average is 100.Example: Denver at 105.8 means prices about 5.8% above average.

Required minimum distribution Accounts

A withdrawal the IRS requires each year from tax-deferred accounts, starting in your 70s. The start age depends on your birth year.

Rule of 55 Accounts

An IRS rule that allows penalty-free withdrawals from your current employer’s plan if you leave that job in or after the year you turn 55.

Savings rate The math

The share of your take-home pay you save: savings divided by savings plus spending. It drives how fast you reach FI more than income alone does.Example: Saving half your take-home pay is about 17 years to FI at 5% real and 4%.

Sequence-of-returns risk Investing

The danger that bad years arrive early in retirement. Withdrawing while prices are down sells more shares, and the shares you sold miss the recovery.

Tax-advantaged account Accounts

An account where the tax rules favor saving, by deducting what you put in now or by not taxing what comes out later. Each type has a yearly contribution limit.

Today’s dollars The math

Amounts stated in what money buys right now, with future inflation already accounted for. Every number on this page is in today’s dollars.

Total return Investing

Price growth plus dividends or interest. The withdrawal-rate research uses total return, not yield.

Treasury bill Investing

Short-term US government debt, a year or less. Its interest is not adjusted for inflation.

Withdrawal rate The math

The share of your portfolio you take out in the first year of retirement, then adjust for inflation after that. Researchers disagree on a safe rate, which is why this page shows a range.Example: 4% of $1,000,000 is $40,000 in year one.

Sourced constants

Each figure is dated. Figures that change every year are marked, and anything taken from press coverage or a secondary recomputation is marked “secondary”. Verify both before relying on them.

Withdrawal-rate research

Return assumption

Saved by age (Fidelity, salary multiples)

Retirement-account medians by age (Fed SCF 2025)

Social Security

Reference yields

Cost of living

Last verified 2026-10-29

Disclaimer

Educational tool, not financial advice. Wanessa Labs FIRE is a free, general-education calculator. It runs entirely in your browser using numbers you enter and publicly available research assumptions shown on the page. It does not know your full situation, does not recommend any security, fund, product, or strategy, and is not a substitute for advice from a licensed professional. Results are hypothetical illustrations, not predictions or guarantees; past market returns do not guarantee future results. Tax, legal, and benefit rules change; verify current figures at irs.gov and ssa.gov. Nothing you enter leaves your device.

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