Kakeibo MethodThe household ledger
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The household ledger

Free calculators

The method, with the arithmetic done

Kakeibo is a practice, not a spreadsheet, but the numbers around it are ordinary division and there is no reason to make you do it. Each tool answers one question properly and runs entirely in your browser.

The instrumentsEach card shows its own real output
How do I split my income the kakeibo way?Kakeibo calculatorIncome in, four envelopes out, with the savings promise taken off the top the way the method insists.You enterIncome, promise, fixed costsIt answersFour envelopes, in method orderOpen the calculator →What does my goal cost per month, week and day?Savings target calculatorAny amount, any deadline. The four figures come back first and the reasoning follows underneath.You enterA target and a deadlineIt answersMonth, fortnight, week and dayOpen the calculator →What shape did my month actually have?Four category splitPut a real month in and read it back as Survival, Optional, Culture and Extra, each as a share of income.You enterA month you already spentIt answersThe shape of it, as four sharesOpen the calculator →Which allocation suits my income better?Kakeibo vs 50/30/20One income, both plans, side by side, with the structural difference spelled out under the numbers.You enterTake home pay and your promiseIt answersBoth allocations, at one widthOpen the calculator →How much can today cost without breaking the plan?Safe to spend todayIncome minus commitments minus the promise, divided by the days left. The number for 4pm on a Thursday.You enterWhat is committed, and the days leftIt answersWhat today can costOpen the calculator →Am I doing better than last month?Savings rateThe one figure that survives a pay rise, plus how many months of spending your balance covers.You enterSaved, spent, and the balanceIt answersA rate, and months of coverOpen the calculator →
Already worked outAll 294 targets →

Common targets, with the monthly, weekly and daily figure and the envelope split already on the page. The full grid runs to 294 worked pages in three currencies, and these are the ones people ask for most:

$10,000 in 12 months$833a month$27.38 a day →$3,000 in 6 months$500a month$16.43 a day →$25,000 in 36 months$694a month$22.82 a day →£5,000 in 12 months£417a month£13.69 a day →£1,000 in 3 months£333a month£10.95 a day →£20,000 in 18 months£1,111a month£36.50 a day →A$7,500 in 6 monthsA$1,250a monthA$41.07 a day →A$50,000 in 36 monthsA$1,389a monthA$45.63 a day →A$500 in 6 monthsA$83.33a monthA$2.74 a day →
Why a kakeibo site has calculators at allThe arithmetic is not the method
01The division

Client side. Nothing is submitted and nothing is stored.

Why a kakeibo site has calculators at all

Because the method is about attention, and arithmetic is the part that does not deserve any. Hani Motoko's readers did this division by hand because there was no alternative in 1904. The reflection is the valuable half, and it is the half a calculator cannot do for you.

So the tools here stop where the method starts. They will tell you what a target costs per day and which envelope it most likely comes out of. They will not tell you whether the trip is worth it, whether the course changed anything, or what you want next year to look like. Those are the four questions, and they are answered in writing, once a month.

02One implementation

Why the figures cannot disagree with each other

Every number on this site comes out of one arithmetic file. The calculators import it into your browser, the worked target pages import it at build time, and the ledger on the front page runs on it too. There is no second copy of the division to drift, which is why a figure you read on a card is the same figure the tool gives you a click later.

Worked in advance294

Savings targets already divided into monthly, weekly and daily figures with the envelope split attached, in 3 currencies. Start from the index if your figure is a common one, or from a calculator if it is not.

The same rule covers what the tools do with your figures, which is nothing. They run in the page, they hold your income and your rent for as long as the tab is open, and they discard both when it closes. There is no request to make, so there is nothing to log.

Common questions

Are these calculators free?
Yes, and there is nothing to sign up for. They run entirely in your browser, which also means nothing you type is sent anywhere, stored or logged.
Do they work offline?
Once a page has loaded, yes. The arithmetic is a few kilobytes of JavaScript on the page itself, with no server call behind it, so a calculator keeps working on a plane or in a basement.
Which one should I start with?
If you are new to the method, start with the kakeibo calculator: it lays out the four envelopes from a single income. If you already have a goal in mind, start with the savings target calculator and work backwards from the date.
Do the calculators agree with the worked pages?
They share one implementation. The interactive tools and the 294 worked savings target pages import the same arithmetic file, so a figure cannot differ between them.
Does a calculator show an answer before I type anything?
Yes. Every one of them opens on a worked example with the figures already filled in and the result already drawn, so you can see what the tool does before deciding whether to put your own numbers in.

The calculators plan. The ledger records.

Every figure on this site assumes the entries are real. Making that easy is what the app is for, with the same four envelopes and the monthly questions built in.

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The Kakeibo app showing a monthly budget with income, expenses and a savings goal in progress