What would be a way of making clear the distinction between 00:00 min:sec format and 00:00 hour:min format? Due to spacing constraints (driven by specific client specs regarding font sizes; this is an embedded HMI), I can neither use full format (00:00:00) nor is there space for a full min:sec / hour:min pseudo-unit.

I'm thinking of using "h" for the hour:min entries and "min" for the "min:sec" entries, but this not really intuitive.

  • 1
    Definitely a duplicate, but sufficiently different that it's useful search fodder and OP doesn't deserve downvotes. Also the answers here are much more concise and generally better IMO.
    – user234461
    Sep 21, 2018 at 12:54

3 Answers 3


You can make something like :




Which is both short and pretty clear.


You can always leave larger unit with one digit and one letter.

0m:00 = minute & second
0h:00 = hour & minute

  • 2
    you don't need the ":" when using a unit for time
    – Luciano
    Sep 21, 2018 at 11:44

Depending on your target locale, ' and " may be understood as abbreviations for seconds and minutes, but that can make h for hour look out of place:


Perhaps use : as a separator for hours and minutes, and ' as a separator for minutes and seconds? Like this:

00'01  1 second
01:00  1 hour
  • +1 for mentioning locale. ' and " for mins and secs is traditional in (some? most?) anglophone locales if we know it's about time; otherwise it's far more common for feet and inches. But 3h30 is commonly used in (Canadian?) French for 3:30 am, not 3.5 hrs duration. I'd recommend having a key somewhere on the screen, showing h:m:s or h:m or m:s to clarify.the format.
    – CCTO
    Sep 21, 2018 at 13:52
  • According to the question, it seems likely there's no space for a key either. At least, that's my reading - I might be wrong. Sep 21, 2018 at 13:58

Not the answer you're looking for? Browse other questions tagged or ask your own question.