Regular Expressions 101

1st Alternative^k[a-z0-9]{9}$

^start of line

kthe literal k (107₁₀ / 153₈ / 6B₁₆) (case insensitive)

Character Class[a-z0-9]{9}

{9}matches exactly 9 characters from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case insensitive)

0-9one character from 0 (48₁₀) to 9 (57₁₀)

$end of line

2nd Alternative^(?:([a-z0-9-_]{1,32})@)?([a-z0-9]{1,64}).kst$

^start of line

Non-Capturing Group(?:([a-z0-9-_]{1,32})@)?

?repeats the group contents below at most once:

Group 1([a-z0-9-_]{1,32})

Character Class[a-z0-9-_]{1,32}

{1,32}matches between 1 and 32 characters from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case insensitive)

0-9one character from 0 (48₁₀) to 9 (57₁₀)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

@the literal @ (64₁₀ / 100₈ / 40₁₆)

Group 2([a-z0-9]{1,64})

Character Class[a-z0-9]{1,64}

{1,64}matches between 1 and 64 characters from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case insensitive)

0-9one character from 0 (48₁₀) to 9 (57₁₀)

.any character (except for line terminators)

kstthe literal text kst (case insensitive)

$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

i modifier: insensitive. Matches without distinguishing uppercase and lowercase letters

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

^k[a-z0-9]{9}$|^(?:([a-z0-9-_]{1,32})@)?([a-z0-9]{1,64}).kst$

New

hugepoopy.kst
buy@hugepoopy.kst
buy_many@hugepoopy.kst
buy@many@hugepoopy.kst
buy.many@hugepoopy.kst
hugepoopy.tst
huuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuugepoopy.kst

khugepoopy
buy@khugepoopy
khuuugepoopy

Regular Expression

Substitution