Take what is in your account, subtract the bills that still have to come out before payday, and divide by the days left. That is your daily allowance. Enter the three numbers and the calculator does it, with a weekly figure too.
The number people get wrong is the middle one. A balance of £420 looks fine until the £60 phone bill and the £45 gym come out on the 20th. Check the direct debit list in your banking app for anything dated before payday and add it up. The household bills template makes this a one-off job.
Make the allowance stick
Move the spendable amount to a separate pot or card and spend only from that.
Recalculate mid-way; a good week early on buys slack later.
If you are here every month, the problem is the month, not the week. Track a full month and find the category that is doing it.
The Income TrackerTrack it free. No account, no bank login.
Money in the account, minus bills still to come out before payday, divided by the days until payday.
What if the answer is negative?
The bills exceed what you have. Move a payment date, use savings if you have them, or contact your bank before a payment fails; unarranged overdrafts are expensive.
Does this replace a budget?
No. It gets you to payday. A monthly ledger shows why you keep needing it, which is the more useful fix.