an address with or without the scheme
Matches an address with or without the scheme. It is anchored at both ends, so the whole string has to match. There are no capture groups.
Pattern
/^(?:https?://)?example\.com$/- Match scope
- the whole string
- Capture groups
- 0
- What it catches in the first example
- example.com
Try it yourself
Type any text and the parts this expression catches are highlighted. It runs in your browser and is never sent anywhere.
example.com
1 match
Examples that match
- example.com
- https://example.com
Examples that do not match
- ftp://example.com
- example.org
Other expressions in this group
^(?:cat|dog)$either one of two words^(?:ab)+$a two-letter group, repeated^(\d{3})-(\d{4})$two parts caught separately^(?:\d{3}-)+\d{4}$grouping without catching^(?<year>\d{4})-(?<month>\d{2})$catching with a name attached(\w)\1the same character twice in a row\b(\w+)\s+\1\bthe same word typed twice^(?:\d{1,3}\.){3}\d{1,3}$an address made of four partsHow 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 an address with or without the scheme?
^(?:https?://)?example\.com$.
Q. Which strings match?
Text like example.com matches; text like ftp://example.com 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.