How do I work out how much to save per month?

Divide the target by the number of months between now and the deadline. That is the whole calculation. The weekly and daily figures are the same division against 52 weeks and 365 days a year, and they matter because a daily number is the one you can act on.

Should I use the monthly or the weekly figure?

Use the one that matches how you are paid. Money moved on the day it arrives is money you never had a chance to spend, so a fortnightly earner should set a fortnightly transfer rather than trying to hold a monthly figure in their head.

Does this include interest on savings?

No, deliberately. Plain division tells you the amount you have to move; a projection tells you what a rate might do. Any interest you earn arrives early, which is the direction you want to be wrong in.

What if the monthly figure is too high?

Move the date before you move the promise. A target that fails in month three teaches nothing; the same target over a longer horizon usually holds. The calculator shows you what each extra few months costs you in per month terms.

Free calculator

Save an amount by a date

The number first, the reasoning after. Enter the target and the horizon, and the four figures that matter come back before you have finished reading this sentence.

The savings target calculatorAny amount, any deadline

$833

a month for 12 months. Set a standing transfer of $840 and you arrive early with a cushion.

The four cadencesOne division, four rhythms

$833Every month
$385Every two weeks
$192Every week
$27.38Every day

Today$0 already saved, $10,000 to reach12 months

Which envelope gives it upThe kakeibo question

Optional$45855% of the monthly figure
Culture$16720% of the monthly figure
Extra$20825% of the monthly figure

A calculator can do the division. Which envelope gives the money up is the question the method leaves with you.

The target: $10,000
Already saved: $0.00
Still to save: $10,000
Weeks to the deadline: 52
Round standing transfer: $840 a month

Start the trim in Optional, which carries about 55 percent of it. Small targets come out of Optional without anything that feels like a sacrifice; larger ones eventually reach Survival, and Survival means fixed costs.

The closest worked page on our grid is $10,000 in 12 months, with the full envelope split.

365 days to run0% of the target already in hand$417 a month, if the deadline moved a year later

Every worked target, already divided →

Why these four figuresOne division, four rhythms

01The daily figure

Small enough to compare against things you actually buy.

Why the daily figure is the useful one

A monthly figure tells you whether a plan is possible. A daily figure tells you which habit has to change to make it happen, and those are different questions. Most people can tell you instantly whether their month has room for another few hundred; almost nobody can tell you where it went last month. The daily number closes that gap because it is small enough to compare against things you actually buy.

That is also why kakeibo asks you to write spending down by hand as it happens rather than reviewing a statement later. The ledger is not bookkeeping. It is the mechanism that makes the daily figure visible while you can still do something about it.

02The envelope

Then the kakeibo question

Once you have the figure, the method asks the question no calculator can answer for you: which of the four envelopes gives it up. Small targets come out of Optional without anything that feels like a sacrifice. Larger ones eventually reach Survival, and Survival means fixed costs, which are decisions with a lead time of months. Saying that plainly is the difference between a plan and a wish.

Already worked out294

Every combination on our grid, envelope split included: 14 targets across 7 horizons in 3 currencies, indexed on the savings targets page.

03When it bites

If the number is uncomfortable

Move the date first. A target that collapses in month three teaches you nothing except that you cannot be trusted, which is both untrue and expensive. The same target over a longer horizon usually holds, and a held plan is what builds the habit that carries the next one. If the date cannot move, the honest options are a smaller target or a structural change, and the savings rate calculator is the quickest way to see which one you are really facing.

Common questions

How do I work out how much to save per month?: Divide the target by the number of months between now and the deadline. That is the whole calculation. The weekly and daily figures are the same division against 52 weeks and 365 days a year, and they matter because a daily number is the one you can act on.
Should I use the monthly or the weekly figure?: Use the one that matches how you are paid. Money moved on the day it arrives is money you never had a chance to spend, so a fortnightly earner should set a fortnightly transfer rather than trying to hold a monthly figure in their head.
Does this include interest on savings?: No, deliberately. Plain division tells you the amount you have to move; a projection tells you what a rate might do. Any interest you earn arrives early, which is the direction you want to be wrong in.
What if the monthly figure is too high?: Move the date before you move the promise. A target that fails in month three teaches nothing; the same target over a longer horizon usually holds. The calculator shows you what each extra few months costs you in per month terms.

The rest of the setEach figure is that tool's own opening answer

How do I split my income the kakeibo way?Kakeibo calculator$1,500left to divide, on a 4,000 monthOpen it →What shape did my month actually have?Four category split$600left over, on that month as spentOpen it →Which allocation suits my income better?Kakeibo vs 50/30/20$800is what the rule would ask forOpen it →How much can today cost without breaking the plan?Safe to spend today$78.57a day, with 14 days still to runOpen it →Am I doing better than last month?Savings rate15%saved, 2.5 months coveredOpen it →All of them, with a preview of each answerThe calculator hub家計簿Every instrument on this siteOpen the hub →

Division is instant. The ledger is the work.

Set the transfer, write the entries, read them back once a month. That sequence is a hundred and twenty years old and it still outperforms good intentions.

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The Kakeibo app showing spending patterns and a goal projection with the monthly amount required