Easily add and subtract hours and minutes.

Enter up to three digits to provide only minutes. For example 90 is interpreted as 1 hour 30 minutes.

Enter exactly four digits to provide hours and minutes. For example 0030 is interpreted as 30 minutes.

The colon separates hour and minutes, so :30 is interpreted as 30 minutes, whereas 2: is interpreted as 2 hours.

After you have entered a time, tap + or -. Then enter the next time. Repeat this as often as required or tap = to get a result. The result is used as the next time, so you can continue with + or -.