The abbreviation for ‘hours’ is hrs. The one for "Minute" is 'min'. It is a unit of measure, which have standard abbreviations, and they do not change in plural nor have a final period. So, the correct abbreviation for minute(s) is "min". My question is: why this discrepancy and not 'hr' in line with 'min'?

  • It's common in both time and positioning for minutes and seconds to abbreviate minutes with an apostrophe ('single quote') and seconds with a quote ("double quote"); In ISO and similar time formatting it's typically colon-joined "hh:mm:ss" eg ":12:43" and "01:02:03". With and without padding and omissions, providing all the colons are included it communicates clearly. The Date toISOString method in browsers prints "2021-07-16T17:36:58.609Z" using this convention.
    – jimmont
    Jul 16, 2021 at 17:42

2 Answers 2


What you have shown are common abbreviations: whether they are standard abbreviations depends on what you mean by standard. Officially, in this context, standard refers to abbreviations that have been officially set out by a national or international body.

I suspect you are wrong in stating that hrs is 'standard' for hours, while min is standard for minute(s). It probably depends who wrote it. I would say that all of the following are commonly used abbreviations:

hour(s): h, hr, hrs
minute(s): m, min, mins


Standard units of measure have standard abbreviations. The hour and minute are not standard units (the standard unit is the second, symbol s), and consequently their abbreviations are not entirely standardised.

Note that where hour is used as a unit, for example in kilowatt-hour, it does have a standard symbol, h. The symbol for kilowatt-hour is kWh.

Note too that there is a difference between symbol (which is standardised) and abbreviation (which is not).

  • 7
    FWIW, I work for a large educational publisher and our house style is to abbreviate "hours" as "h". We see "hr" or "hrs" all the time, and we will always change it to "h" Sep 29, 2013 at 3:28
  • While the minute and the hour are not standard SI units, they are accepted for use together with SI units. The standard symbol for minutes is min while for hours it is h. See here: bipm.org/en/publications/si-brochure/table6.html
    – Ariel
    Jun 13, 2019 at 15:40

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