Screen-time borrowing calculator

How the calculation works

1. Tomorrow = normal allowance − borrowed minutes. 60 − 10 = 50.
2. A minimum protects tomorrow. Tomorrow never drops below the minimum you set. Anything below it is absorbed, not carried into the following day.
3. A daily cap limits borrowing. You cannot borrow more than your cap in one day, or build up more debt than your plan allows.
4. Optional split repayment. Spread repayment over two or three days; earlier days take any remainder (10 minutes over three days = 4 + 3 + 3).
5. No interest, no multipliers. Every borrowed minute is repaid exactly once. Unused borrowed minutes go back if you stop early.

These are the same rules the Time Debt app uses. The calculator is an example; only the app, using Apple's Screen Time permission, can apply a limit on your iPhone.

Related: build a free screen-time plan · how Time Debt works · how iPhone app blockers work

Questions

What happens when I borrow screen time?

You get extra minutes now and the same number of minutes is removed from tomorrow's allowance, or spread over the next two or three days if you chose that. You see the result before confirming.

Can borrowed time make tomorrow's allowance zero?

Only if you set the minimum to zero. With a minimum of 30 minutes, tomorrow never drops below 30 minutes, whatever you borrowed.

Is there interest on borrowed minutes?

No. There is no interest, no multiplier and nothing compounds. It is never real money.

What if I stop using the extra time early?

In the Time Debt app, ending a borrowed session early returns the unused minutes to tomorrow.