Regular expressions·two parts caught separately

two parts caught separately

Matches two parts caught separately. It is anchored at both ends, so the whole string has to match. There are 2 capture groups.

Pattern
/^(\d{3})-(\d{4})$/
Match scope
the whole string
Capture groups
2
What it catches in the first example
123-4567

Try it yourself

Type any text and the parts this expression catches are highlighted. It runs in your browser and is never sent anywhere.

123-4567

1 match

Examples that match

  • 123-4567

Examples that do not match

  • 1234567
  • 12-345

Other expressions in this group

How to read this

  • With ^ and $ around it, the whole string must match; without them the match can sit anywhere. Always anchor an expression you use for validation.
  • Round brackets ( ) capture what they wrap. When you only need grouping, write (?: ) so the numbering of later groups does not shift.
  • Every expression here is checked against its examples. Even so, "looks like an email" and "is a real inbox" remain different questions.
  • Nested open-ended repeats such as (a+)+ can blow up on certain inputs. Look for that shape before pasting someone else’s expression into your code.

Frequently asked questions

Q. What is the regex for two parts caught separately?

^(\d{3})-(\d{4})$.

Q. Which strings match?

Text like 123-4567 matches; text like 1234567 does not.

Q. Does the whole string have to match?

Yes. It is wrapped in ^ and $, so nothing but a full match passes.

Q. How do I use what it caught?

There are 2 capture groups, so you can read them from match[1] onwards.