Regular Expressions 101

(?i)applies the following effective flags to the remainder of the pattern: gmi

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

^start of line

Negative Lookahead(?!(?:.*[a-z]){4})

Non-Capturing Group(?:.*[a-z]){4}

{4}repeats the group contents below exactly 4 times:

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

Character Class[a-z]

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

Non-Capturing Group(?:.*[a-z].*){1,3}

{1,3}repeats the group contents below between 1 and 3 times:

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

Character Class[a-z]

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

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

Regular Expression

(?i)^(?!(?:.*[a-z]){4})(?:.*[a-z].*){1,3}$

New

gut
ok
aa
na
N/A
x
c
Nil
wu
No.
E
A
I
k k
H
o
K
N
Y
Top
OK了
m
| yes
N/A |
t | T
t | T
| idk
| wsq
t | T
ｂ | n

gut
ok
aa
na
N/A
x
c
Nil
wu
No.
E
A
I
k k
H
o
K
N
Y
Top
OK了
m
| yes
N/A |
t | T
t | T
| idk
| wsq
t | T
ｂ | n