RegExr
Tool for creating, testing, and learning about Regular Expressions
RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp). RegExr was created by gskinner.com, and is proudly hosted by Media Temple. Edit the Expression & Text to see matches. Roll over matches or the expression for details. PCRE & JavaScript flavors of RegEx are supported. Validate your expression with Tests mode. The side bar includes a Cheatsheet, full Reference, and Help. You can also Save & Share with the Community, and view patterns you create or favorite in My Patterns. Explore results with the Tools. Replace & List output custom results. Details lists capture groups. Explain describes your expression in plain English. It provides full RegEx Reference with help & examples. Undo & Redo with ctrl-Z / Y in editors. Search for & rate Community Patterns. You can also group multiple tokens together and create a capture group for extracting a substring or using a backreference.