Regex Pal

Dan's Tools

htaccess language redirect

this works with sites, which ALWAYS redirect from / to e,g, /en/. just repeat RewriteCond %{HTTP:Accept-Language} ^(((?!(de|es|fr|it))[^,])*(,\2[^,]*)?,)*de [NC] RewriteRule ^$ /de/ [L,R=301] for all available languages (change *de and /de/) followed by RewriteRule ^$ /en/ [L,R=301]


Top Regular Expressions

Cheat Sheet

Character classes
. any character except newline
\w \d \s word, digit, whitespace
\W \D \S not word, digit, whitespace
[abc] any of a, b, or c
[^abc] not a, b, or c
[a-g] character between a & g
^abc$ start / end of the string
\b word boundary
Escaped characters
\. \* \\ escaped special characters
\t \n \r tab, linefeed, carriage return
\u00A9 unicode escaped ©
Groups & Lookaround
(abc) capture group
\1 backreference to group #1
(?:abc) non-capturing group
(?=abc) positive lookahead
(?!abc) negative lookahead
Quantifiers & Alternation
a* a+ a? 0 or more, 1 or more, 0 or 1
a{5} a{2,} exactly five, two or more
a{1,3} between one & three
a+? a{2,}? match as few as possible
ab|cd match ab or cd