How much can I spend a day until payday?
Money left, minus bills due before payday, minus what you want to save. Divide that by the days until payday, counting today.
$840 left and 28 days to go is $30 a day. Spend less and tomorrow gets more. Spend more and tomorrow gets less.
I'm David, and I make DaySpend, an iPhone app that works this number out for you. The sum below works fine on paper too, and it is the same rule the app runs on.
Last checked 27 September 2026.
Work it out in 4 steps
- Start with what you have. The money in your account today, or the part of your pay you keep for everyday spending.
- Take out bills due before payday. Only the ones that come off between now and payday. Rent that already went out is already gone.
- Take out what you want to save. If you move it at the end of the month, it still has to come out of this money.
- Divide by the days until payday. Count today, stop the day before payday.
Example: today is 27 September, payday is the 25th
| Money in your account today | $1,000 |
| Bills still due before payday (phone $40, electricity $80) | - $120 |
| What you want to save this month | - $40 |
| Left to spend | $840 |
| Days until payday, counting today (27 September to 24 October) | 28 |
| Safe to spend each day | $30 |
So you can spend $30 today without touching the phone bill, the electricity, or the $40 you are putting away. The same sum works in rand, pounds, euros, or anything else.
What happens after a big day
You will not spend exactly $30 every day. Some days it is $5, and some days it is the weekly shop. The money has to balance out before payday, and there are 2 honest ways to do it.
- Spread it over every day left. Divide what is left by the days left, every day. After spending $75 in 2 days, $825 over 26 days is about $31.73. The hit is so thin you barely feel it.
- Carry it into tomorrow. Leftover money moves to the next day, and so does overspending. You feel a big day the day after, and a quiet day earns it back. This is what DaySpend does.
Here is the second way with the same $30 a day:
| Day | Safe today | Spent | Why |
|---|---|---|---|
| Day 1 | $30 | $20 | $10 left over |
| Day 2 | $40 | $55 | the $10 carried in, then a big shop |
| Day 3 | $15 | $0 | the extra $15 came off today |
| Day 4 | $45 | - | a quiet day earned it back |
The rule behind it: today's number is $30 times the days so far, minus everything spent so far. On day 3 that is $90 minus $75, which is $15. Both ways land on the same total by payday. I prefer the second, because a number that drops tomorrow changes what I do today.
4 mistakes that break the number
Counting payday itself.
Your pay lands that morning, so the old money only has to last until the day before. Count from today up to the day before payday.
Forgetting bills that come off before payday.
If the phone bill goes out on the 1st and you get paid on the 25th, that money is already gone. Take it out before you divide.
Using the calendar month when you are paid mid-month.
If you are paid on the 25th, your month runs from the 25th to the 24th. A budget that resets on the 1st will be wrong for most of it.
Working it out once and never again.
The number is only useful if it moves when you spend. A sum on the back of a receipt goes stale the first time you buy lunch.
Paid weekly or every 2 weeks? It is the same sum over 7 or 14 days.
Let your phone do the sum
DaySpend is my app, so weigh this part with that in mind. You tell it your budget and the day you get paid, and it shows what is safe to spend today. Log a purchase and the number updates. Leftover money rolls into tomorrow, exactly like the table above.
- Runs payday to payday: a day of the month, a day of the week, or a custom number of days.
- No bank login. Your budgets and expenses stay on your phone.
- A Home Screen widget shows today's number without opening the app.
- Free for 1 budget. Plus adds more budgets, money in, and the Lock Screen widget for $2.99 a month, $19.99 a year, or $39.99 once, with a 7-day free trial.
Common questions
How do I work out how much I can spend a day until payday?
Take the money you have now, subtract any bills that will come off before payday and anything you want to save, then divide what is left by the number of days until payday. Count today, but not payday itself. $840 over 28 days is $30 a day.
Should I count today when I work out days until payday?
Yes. Today is a day you can still spend on. Count from today up to the day before payday. From 27 September to a payday on 25 October is 28 days.
What happens if I spend more than my daily amount?
The money has to come from somewhere, so a later day gets less. You can take it all off tomorrow, which you will notice, or spread it over every day left, which you will barely notice. DaySpend takes it off the next day's number, and a quiet day earns it back.
How do I do this if I am paid weekly or every 2 weeks?
Same sum, shorter period. Divide the money for the week by 7, or the money for the fortnight by 14. DaySpend has weekly and custom-length budgets, so a 14-day pay cycle works the same way as a monthly one.
Is there an app that tells me how much I can spend each day until payday?
DaySpend does exactly this on iPhone. You enter your budget and the day you get paid, and it shows what is safe to spend today. It updates as you log purchases and carries leftover money into tomorrow. No bank login, and your money data stays on your phone. It is free to download, and it is my app.