text that must contain this sign
Matches text that must contain this sign. It is anchored at both ends, so the whole string has to match. There are no capture groups.
Pattern
/^(?=.*@).+$/- Match scope
- the whole string
- Capture groups
- 0
- What it catches in the first example
- a@b
Try it yourself
Type any text and the parts this expression catches are highlighted. It runs in your browser and is never sent anywhere.
a@b
1 match
Examples that match
- a@b
- x@y.com
Examples that do not match
- ab
- plain
Other expressions in this group
\d+(?= dollars)a number followed by a certain word^(?!admin$).+$anything except this one word(?<=\$)\d+a number preceded by a certain sign(?<!\$)\b\d+a number without that sign in front^(?=.*[A-Z])(?=.*\d)(?=.*[a-z]).{8,}$eight or more characters with upper, lower and a digit^(?!.* ).+$text with no double space anywhere\B(?=(\d{3})+(?!\d))the spot where a thousands comma goesHow 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 text that must contain this sign?
^(?=.*@).+$.
Q. Which strings match?
Text like a@b matches; text like ab 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 no capture groups, so only the whole match (match[0]) comes back. Wrap the part you need in brackets to capture it.