Click on a radical to add it to the kanji query input field.
foo matches "foo".
. ^ $ * + ? { } [ ] \ | ( )
allow matching using sophisticated patterns and rules; they
are escaped by preceding them with a backslash; e.g.
\\ matches an actual backslash.
. matches any character (except newline); e.g.
ba. matches "bar", "baz", etc.
^ matches at the start of a line; e.g.
^foo matches "foo" at the start of a line.
$ matches at the end of a line; e.g.
foo$ matches "foo" at the end of a line.
\b matches at a "word boundary" (the start or
end of a "word"); e.g. \bbar\b matches "bar" in
"foo bar baz", but not in "foobarbaz"; \B is
its complement.
* matches the preceding thing zero or more
times; e.g. fo* matches "f", "fo", "foo", etc.
+ matches the preceding thing one or more
times; e.g. fo+ matches "fo", "foo", etc.
? matches the preceding thing optionally; e.g.
fo? matches "f" or "fo".
{m,n} (or just {m} instead of
{m,m}) matches the preceding thing
m to n times; e.g.
fo{2,4} matches "foo", "fooo", or "foooo".
[...] is a character class; e.g.
[a-z] matches "a" through "z";
[あいうえお] matches "あ", "い", "う", "え", or
"お".
[^...] is a complementing character class; e.g.
[^a-z] matches anything but "a" through "z".
\d matches any decimal digit (equivalent to
[0-9]); \D is its complement
(equivalent to [^0-9]).
\s matches any whitespace character;
\S is its complement.
\w matches any alphanumeric (i.e. "word" or
"letter") character; \W is its complement.
| is alternation; e.g. foo|bar|baz
matches "foo", "bar", or "baz".
(...) is grouping; e.g. ab*
matches "a", "ab", "abb", etc. whereas (ab)*
matches "", "ab", "abab", etc.; ^foo|bar$
matches "foo" at the beginning of a line or "bar" at the
end, whereas ^(foo|bar)$ matches either "foo"
or "bar" as a whole line; a backslash followed by the number
of the group (starting from 1) can be used later in the
pattern to refer back to what it (actually) matched; e.g.
[a-z]{2} matches "aa", "ab", "za", etc. whereas
([a-z])\1 matches "aa", "bb", etc. (but not
"ab" or "za").
\p{...} matches a unicode property; e.g.
\p{Han} matches kanji,
\p{Hiragana} matches hiragana, and
\p{Katakana} matches katakana; \P
is its complement.
\bcat\b matches "cat" in "the cat" (but not in
e.g. "indicates").
^cat\b matches "cat" in "cat" or "cat (esp. the
domestic cat, Felis catus)" (but not in e.g. "category").
^cat$ matches "cat" exactly.
^猫\p{Han}$ matches "猫" followed by exactly
one other kanji.
^(\p{Han})\1$ matches e.g. "人人".