Column formatted as h]:mm:ss defaults to AMPM time upon editing cell

This behavior is expected in Excel on Mac. Even though the column is formatted as [h]:mm:ss, Excel still treats the value internally as a standard time value, so when you edit the cell it may display in AM/PM format.

As a workaround, we recommend entering durations with the hour included (for example 0:10:05 instead of 10:05) and keeping the column formatted as [h]:mm:ss. The displayed values and calculations will still work correctly as elapsed time.

Tipps…

Avoid h:mm:ss Format: This format resets to 0 after 24 hours (e.g., 25:30:00 becomes 1:30:00). Use [h]:mm:ss for durations over 24 hours.

Check for Hidden Formatting: If the issue persists, ensure no conditional formatting or data validation is overriding the [h]:mm:ss format.

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