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Incolator/Salary & income/The Work-Optional Number

Salary & income · 2 min

The Work-Optional Number

There is a number at which employment becomes a preference. It is not mystical: annual spending divided by a withdrawal rate, a convention people have argued about for thirty years. This instrument computes yours, shows how far along you are, and dates the crossing at your current savings pace — under assumptions you can see and change.

Currency-agnostic · symbol only Rules version 1.0 Reviewed July 2026

Compounding arithmetic under stated conventions — not financial advice, not a plan. Sequence risk, taxes and real life are larger than any single rate.

Your details

Σ/ yr

Net annual spending in the optional years — today's money.

The share of the pile spent each year. 4% is the famous study; 3–3.5% is what caution and longer horizons argue for. All three are conventions.

Σ

Liquid, invested capital working toward the number. Not the house you live in.

Σ/ mo

What reliably reaches the invested pile each month.

% / yr

After inflation — that's what 'real' means, and why the number is in today's money. 4% real is an unheroic long-run figure for diversified capital.

Everything is calculated in your browser as you type. Nothing you enter is sent or stored, and no account is needed.

Your result

Early passage.

$3,428,571

the number at your spending and a 3.5% convention

The ledger

The work-optional number
Where you stand today
Progress
Years to the crossing, at this pace
One year of spending, in pile terms

Three conventions, same life

At a withdrawal rate ofThe numberYears to it

What moves this result

Worth checking

Spending is the lever nobody prices: every 10,000 of permanent annual spending adds roughly thirty times that to the number. The cheapest year you'll ever buy is the one you don't need to fund.

Sequence risk lives outside this table. A bad first decade of withdrawals can break a plan the average return said was safe — which is why the conservative conventions exist.

The number is in today's money because the return is real. Quote it nominal and it grows every year — the arithmetic is honest only if both sides stay real.

Common questions

How is the work-optional (financial independence) number calculated?
Annual spending divided by a withdrawal rate. At $120,000 of net spending and a 3.5% convention, the number is about $3.43M; at the classic 4%, $3M. The withdrawal rate is a convention with a thirty-year argument behind it — this instrument shows all three so the choice is visible.
Is the 4% rule still valid?
It's the original convention from the Trinity-era studies of US markets, and it held historically for 30-year retirements. Longer horizons, lower expected returns and non-US portfolios push careful planners toward 3–3.5%. None of them is a law; all of them are on this page's scenario table.
How many years until I can stop working?
Depends on three levers: what you spend, what you save monthly, and the real return. The instrument solves the compounding equation for your inputs and prints the year — and the drivers row shows which lever moves it most, which is almost always spending.
How this is calculated

Everything below is calculated from your inputs except the real return, an assumption you control. All figures are in today's money.

number = spending / withdrawal_rate years = ln( (number·g + s) / (now·g + s) ) / ln(1+g) where g = real return, s = annual savings / g progress = now / number

The gauge reads progress toward the number, the line at 100% — the crossing. The verdict bands are the house's, not physics: under a third, early passage; a third to two-thirds, mid-crossing; past two-thirds, the far shore is visible.

Limitations. A single withdrawal rate compresses thirty years of market history and argument into one figure; taxes on withdrawals, pensions arriving later, and spending that changes with age are all outside. This is the sketch that makes the real planning conversation concrete — not the plan.