Regular Expressions 101

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/
1?\(?([0-9]{3})\)?[-.\s]?([0-9]{3})[-.\s]?([0-9]{4})
/
1
matches the character 1 with index 4910 (3116 or 618) literally (case sensitive)
\(
matches the character ( with index 4010 (2816 or 508) literally (case sensitive)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
1st Capturing Group
([0-9]{3})
Match a single character present in the list below
[0-9]
{3} matches the previous token exactly 3 times
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
\)
matches the character ) with index 4110 (2916 or 518) literally (case sensitive)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[-.\s]
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
-.
matches a single character in the list -. (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
2nd Capturing Group
([0-9]{3})
Match a single character present in the list below
[0-9]
{3} matches the previous token exactly 3 times
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
Match a single character present in the list below
[-.\s]
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
-.
matches a single character in the list -. (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
3rd Capturing Group
([0-9]{4})
Match a single character present in the list below
[0-9]
{4} matches the previous token exactly 4 times
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/

Test String

Substitution

Processing...