Regular Expressions 101

Explanation
Pro

1st Alternative^1\d{10}$

^start of line

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

\d{10}a digit, repeated exactly 10 times

$end of line

2nd Alternative^(\d{3,4}[-\/]?)?\d{7,8}([-\/]\d{2,4})?$

^start of line

Group 1(\d{3,4}[-\/]?)?

?repeats the group contents below at most once:

\d{3,4}a digit, repeated between 3 and 4 times

Character Class[-\/]?

?matches at most one character from the set below:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

\d{7,8}a digit, repeated between 7 and 8 times

Group 2([-\/]\d{2,4})?

?repeats the group contents below at most once:

Character Class[-\/]

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

\d{2,4}a digit, repeated between 2 and 4 times

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

^1\d{10}$|^(\d{3,4}[-\/]?)?\d{7,8}([-\/]\d{2,4})?$

New

1234567
12345678
01212345678
012-12345678
1234-1234567
1234-12345678
012/1234567
012/12345678
1234/1234567
1234/12345678
13585881145
012-1345678-1234

1234567
12345678
01212345678
012-12345678
1234-1234567
1234-12345678
012/1234567
012/12345678
1234/1234567
1234/12345678
13585881145
012-1345678-1234