The best online regular expression / RegEx testers and builder-tools as of 2013

High level programming without the power of regular expressions would be much less fun. They may often be crucial, when drafting a first program on a tight schedule.

Regular expressions are thus likely Donald Knuth's best friend, whose famous quote is:
premature optimization is the root of all evil

The top choices for building regular expressions are listed first.

  • - fast, versatile, bootstrap based - responsive design, works on mobiles, many options. multiple input-string testing. multiple language support:  Java, PHP, Ruby, .Net and python



Notice: Adobe Flash based options were omitted from the list. XnView was used for screen-captures.