Regular expressions·a hex colour inside running text

a hex colour inside running text

Matches a hex colour inside running text. It finds the match anywhere inside the text. There are no capture groups.

Pattern
/#[0-9a-fA-F]{6}\b/
Match scope
anywhere inside the text
Capture groups
0
What it catches in the first example
#ff0000

Try it yourself

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

color: #ff0000; #00FF00 background

2 matches

Examples that match

  • color: #ff0000;
  • #00FF00 background

Examples that do not match

  • #ff00
  • no colour

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 a hex colour inside running text?

#[0-9a-fA-F]{6}\b.

Q. Which strings match?

Text like color: #ff0000; matches; text like #ff00 does not.

Q. Does the whole string have to match?

No. It finds the part anywhere inside the text. Add ^ and $ around it if you want a whole-string check.

Q. How do I use what it caught?

There are no capture groups, so only the whole match (match[0]) comes back. Wrap the part you need in brackets to capture it.