Test regular expressions in real-time with match highlighting and capture groups.
.Any character\dDigit [0-9]\wWord char\sWhitespace\bWord boundary*0 or more+1 or more?0 or 1{n,m}n to m times(abc)Capture group(?:abc)Non-capturea|bAlternation[abc]Char class^Start of string$End of string(?=...)Lookahead(?<=...)Lookbehind