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Asked: 2026-05-15T09:22:15+00:00

Anyone have a good regex for Age verification? I have a date field where

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Anyone have a good regex for Age verification?

I have a date field where I am validating that what the user enters is a date.

basically I wanted to figure out if that date is valid, and then further refine the date to be within x number of years

Perhaps this may be too complicated to tack onto whatever I have too far, but I figured it wouldn’t be.

^([1][012]|[0]?[1-9])[/-]([3][01]|[12]\d|[0]?[1-9])[/-](\d{4}|\d{2})$
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  1. Editorial Team

    I’m a big fan of regexes, and of course it’s possible to check a date against a “legal range” using regexes.

    BUT:

    Matching a valid date (without fancy stuff like checking for leap years) is fairly trivial but tiresome by regex – a tool for constructing regexes like RegexMagic will do this for you quickly:

    (?:0?2[/.-](?:[12][0-9]|0?[1-9])|(?:0?[469]|11)[/.-](?:30|[12][0-9]|0?[1-9])|(?:0?[13578]|1[02])[/.-](?:3[01]|[12][0-9]|0?[1-9]))[/.-][0-9]{4}

    is what RegexMagic generates for MM/DD/YYYY date validation without imposing limits on date ranges (i.e. 02/31/2020 won’t match, 01/31/4500 will).

    This is already ugly and probably quite hard to figure out if you’re the one inheriting this code.

    The second problem, namely validating against a predefined date range is even uglier. It can be done, but

    1. you’d need to change your regex
      every single day – after all, every
      day, someone turns 18, don’t they?
      and

    2. the regex would get even more unwieldy. To allow anything from 06/10/1992 until
      06/10/2010, you get

    this monster of a regex.

    0?6[/.-](?:30|[12][0-9])[/.-]1992|(?:(?:0?9|11)[/.-](?:30|[12][0-9]|0?[1-9])|
(?:0?[78]|1[02])[/.-](?:3[01]|[12][0-9]|0?[1-9]))[/.-]1992|0?6[/.-](?:10|0?[1-9])
[/.-]2010|(?:0?2[/.-](?:[12][0-9]|0?[1-9])|0?4[/.-](?:30|[12][0-9]|0?[1-9])|0?
[135][/.-](?:3[01]|[12][0-9]|0?[1-9]))[/.-]2010|(?:0?2[/.-](?:[12][0-9]|0?[1-9])|
(?:0?[469]|11)[/.-](?:30|[12][0-9]|0?[1-9])|(?:0?[13578]|1[02])[/.-](?:3[01]|
[12][0-9]|0?[1-9]))[/.-](?:200[0-9]|199[3-9])

    (linebreaks included for “clarity”).

    Tomorrow, you’ll need

    0?6[/.-](?:30|2[0-9]|1[1-9])[/.-]1992|(?:(?:0?9|11)[/.-](?:30|[12][0-9]|0?[1-9])|
(?:0?[78]|1[02])[/.-](?:3[01]|[12][0-9]|0?[1-9]))[/.-]1992|0?6[/.-](?:1[01]|0?[1-9])
[/.-]2010|(?:0?2[/.-](?:[12][0-9]|0?[1-9])|0?4[/.-](?:30|[12][0-9]|0?[1-9])|0?
[135][/.-](?:3[01]|[12][0-9]|0?[1-9]))[/.-]2010|(?:0?2[/.-](?:[12][0-9]|0?[1-9])|
(?:0?[469]|11)[/.-](?:30|[12][0-9]|0?[1-9])|(?:0?[13578]|1[02])[/.-](?:3[01]|
[12][0-9]|0?[1-9]))[/.-](?:200[0-9]|199[3-9])

    Notice the subtle difference?

    In short, as all the others have pointed out: This is not something you want to use a regular expression for. Even if you can.

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