emichswimr,
If you know that your input string will only be a sequence of digits, then use pg's solution of anchoring with ^ and $. If you need to match within a string, then one of these may help. 

/\b\d{5}\b/;
or
/\D\d{5}\D/;
or
/\s+\d{5}\s+/;

[download]
  • The first one breaks on word boundaries (any character not in \w)
  • The second one breaks on any non digit
  • The third one breaks on white spaces

    Cheers - L~R

    Update: Changed introduction to explain why these solutions may be more flexible then the ones that anchor with ^ and $

    In reply to Re: specific numbers of digits by Limbic~Region
    in thread specific numbers of digits by emichswimr

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