THE WALKAWAY NUMBER · CHAPTER 1 · THE FIRST PASS, NOT THE FINAL WORD

The Napkin Calculator

Build a lower-bound target, a conservative range, the gap, and a first-pass timeline in about fifteen minutes.

Output: One dated 25x, 30x, and 33x target range with nine compound-growth timelines, a selected planning case, and written boundaries.

Time: 15 minutes for the first pass; revisit after Chapters 3, 6, 9, and 10

Target rangeUnresolved

Invested assetsUnresolved

Annual contributionsUnresolved

Selected timelineUnresolved

Professional reviewNo flag selected

Complete the money inputs and choose a planning case.

The calculation still has an unresolved money field, selected case, date, or boundary.

The napkin has rules

Blank money fields stay unresolved. Enter 0 when a category truly has no balance. A blank isn't a secret zero wearing business casual.

Don't divide the gap by annual saving and call it a forecast. That shortcut ignores growth on the starting balance and every future contribution.

A projection is a dated planning estimate. It doesn't guarantee a future result or turn 25x into an automatic choice for a younger reader.

1. Spending, age, and horizon

Use expenses, not income. Chapter 3 replaces this first-pass estimate with an audit.

Calculation dateEstimated annual household spendingCurrent ageIntended work horizon, years from now

2. Invested assets

Home equity stays out unless the use plan is specific and realistic. Exclude home equity unless the plan names a specific, realistic way to use it.

Retirement accountsEnter 0 if none.Brokerage accountsEnter 0 if none.Investable cash beyond the emergency reserveEnter 0 if none.Include a specific, realistic home-equity plan.

3. Annual contributions

Annual employee contributionsEnter 0 if none.Annual employer matchEnter 0 if none.Annual IRA contributionsEnter 0 if none.Other annual investingEnter 0 if none.

Invested assets usedUnresolved

Annual contributionsUnresolved

ConventionMonthly compounding with contributions at month end

4. The target range and nine timelines

~ marks an estimate. Each case uses monthly compounding with contributions at month end.

25x · Lower bound

Unresolved

Gap unresolved

3% realUnresolved

5% realUnresolved

7% realUnresolved

30x · Planning target

Unresolved

Gap unresolved

3% realUnresolved

5% realUnresolved

7% realUnresolved

33x · Conservative target

Unresolved

Gap unresolved

3% realUnresolved

5% realUnresolved

7% realUnresolved

5. Select the planning case

Selected multiplierSelected real returnWhy this real-return assumption is supportable

The result is a dated planning estimate. It isn't a verdict, a guarantee, or permission to ignore concentration risk because the number happens to fit on one line.

6. Label the boundary

Write what the target assumes. Silence isn't an assumption. It's a missing line item.

Future earnings after full-time employmentHealth coverage and unusual health costsSocial Security assumptionTax assumptionSpending flexibility

Professional-review flags

One checked flag means the calculation should travel to the qualified professional who owns that decision.

Calculation convention

Target = annual spending × multiplier. Gap = target less invested assets, floored at zero for display; any excess is shown as surplus. Timelines use monthly compound growth and end-of-month contributions at 3%, 5%, and 7% real.

The projection doesn't model taxes, Social Security, health costs, or earnings after full-time employment. Those belong in the written boundary until later chapters replace them with better evidence.

Completion test

Complete every money input with a number, select one multiplier and real-return case, and write all five planning boundaries. Enter zero when a money category truly has no balance.

Monday Move

Write the spending estimate first. Income will volunteer for the role because income enjoys being invited to meetings where it doesn't belong.

This tool stays in this browser with LocalStorage until you clear it.