Regular Expressions 101

^start of line

Group 1((b+.*)|((a(aa)*)?b*)|a*((bbb)*|bb(bbb)*)|(.*a+))

1st Alternative(b+.*)

Group 2(b+.*)

b+the literal b (98₁₀ / 142₈ / 62₁₆) (case sensitive), repeated at least once

.*any character (except for line terminators), repeated any number of times

2nd Alternative((a(aa)*)?b*)

Group 3((a(aa)*)?b*)

Group 4(a(aa)*)?

?repeats the group contents below at most once:

athe literal a (97₁₀ / 141₈ / 61₁₆) (case sensitive)

Group 5(aa)*

*repeats the group contents below any number of times:

aathe literal text aa (case sensitive)

b*the literal b (98₁₀ / 142₈ / 62₁₆) (case sensitive), repeated any number of times

3rd Alternativea*((bbb)*|bb(bbb)*)

a*the literal a (97₁₀ / 141₈ / 61₁₆) (case sensitive), repeated any number of times

Group 6((bbb)*|bb(bbb)*)

1st Alternative(bbb)*

Group 7(bbb)*

*repeats the group contents below any number of times:

bbbthe literal text bbb (case sensitive)

2nd Alternativebb(bbb)*

bbthe literal text bb (case sensitive)

Group 8(bbb)*

*repeats the group contents below any number of times:

bbbthe literal text bbb (case sensitive)

4th Alternative(.*a+)

Group 9(.*a+)

.*any character (except for line terminators), repeated any number of times

a+the literal a (97₁₀ / 141₈ / 61₁₆) (case sensitive), repeated at least once

$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.

Search reference

Regular Expression

^((b+.*)|((a(aa)*)?b*)|a*((bbb)*|bb(bbb)*)|(.*a+))$

New

aabbbb
aaaab

aabb

abbbb
aaabbbb
bbbb

bbbb
bbbbb
bbbbbbb

aa
aaaabb
aaaabbb
aaaabbbbb

abbbb
baabbbb
aabbbba
aabbb
aa
bbbb
b
baaaa
baaba