家計簿 · the household ledger
Budgeting that writes itself down
Kakeibo is four spending categories, one savings promise made before the month starts, and four questions answered when it ends. Published in 1904, still the most honest budgeting method there is, and we have done the arithmetic around it so you can get on with the noticing.
6 free calculators294 worked targetsNo email wall

Nothing on this site repeats the claim that kakeibo saves 20 to 35 percent. We went looking for a primary source and could not find one.
Four envelopes, not thirty categories
Few enough to hold in your head at the counter, which is where the decision actually gets made.
The part a computer should do
Free, instant, and running entirely in your browser: nothing you type on this site is sent anywhere.
Or start from the number you are saving for
Every common target worked out per month, per week and per day, then framed through the four envelopes: which one gives the money up, and what the plan asks of your income. 14 amounts across 7 horizons in 3 currencies.

The ledger, kept between reflections
The method needs the entry to happen at the counter rather than from memory on Sunday night. That is the one job the app exists to do.
The method, not a category tree
Every expense goes into Survival, Optional, Culture or Extra, the way the ledger has worked since 1904.
What today can cost
Income minus commitments minus your promise, divided by the days that are left, kept current as you record.
A target with a date on it
Set the amount and the deadline and the monthly figure follows, with the running total held against it.
The four questions at month end
Asked in writing and kept afterwards, so a year of months becomes something you can actually read back.



SortingThe four kakeibo categories explainedSurvival, Optional, Culture and Extra, with a working list of everyday expenses sorted into each one and the awkward cases argued out.9 min read
Modern moneyHow to do kakeibo with a credit card and digital paymentsThe main practical objection to a 1904 paper method, answered properly: cards, subscriptions, buy now pay later, and the two week lag between the decision and the money.8 min read
ReflectionThe four kakeibo questions, and prompts for the weekly and monthly reviewThe four questions in the order the method asks them, plus a short weekly check and a longer monthly reflection you can work through in fifteen minutes.10 min readChoosing between methods instead? Kakeibo compared with 50/30/20, YNAB, envelopes and cash stuffing.
Four categories, four questions, one honest month
Start by measuring a normal month and changing nothing. The app keeps the envelopes and the totals so the only work left is the noticing.
