Skip to content
SPECIFICTION
Get listed

RegExr

regexr.com

Free plan Web
Visit regexr.com
Spec score 7.6 #9 of 23 in Regular Expression Testers

What it is

RegExr is a free web tool for learning, building, and testing regular expressions. It supports JavaScript and PHP/PCRE expressions, with results that change as you type. Hovering over a match or expression reveals details, and the Explain tool describes an expression in plain English. Tests mode lets users assemble examples that an expression should match or reject. Replace and List produce custom outputs, while Details shows capture groups. Learning resources include a cheatsheet, reference, help pages, and examples. Users can search and rate Community Patterns, then save and share expressions. Signing in keeps favorites and patterns in My Patterns. A saved expression gets a public link, and a Community-shared copy cannot be edited or deleted. The listed RegExr plan costs nothing. The project README credits Grant Skinner and gskinner.com as creators and identifies this version as GPL v3 licensed. It directs issue and feature requests to GitHub and regular-expression questions to Stack Overflow.

Spec sheet

Purpose
RegExr is an online tool to learn, build, and test regular expressions.Read 5 Oct 2026 · regexr.com
Support
The project README directs users to GitHub for issues and feature requests and Stack Overflow for regular-expression questions.Read 5 Oct 2026 · github.com
License
The project README says this version of RegExr is licensed under GPL v3.Read 5 Oct 2026 · github.com
Account storage
Signing in lets users persist favorites and patterns, which are shown in My Patterns.Read 5 Oct 2026 · regexr.com
Community
Users can search for and rate Community Patterns.Read 5 Oct 2026 · regexr.com
Creator
The project README says RegExr was created by Grant Skinner and gskinner.com.Read 5 Oct 2026 · github.com
Explain
The Explain tool describes an expression in plain English.Read 5 Oct 2026 · regexr.com
Learning resources
The site includes a cheatsheet, full reference, help, and examples.Read 5 Oct 2026 · regexr.com
Live results
Results update in real time as you type.Read 5 Oct 2026 · regexr.com
Match details
Rolling over a match or expression displays details.Read 5 Oct 2026 · regexr.com
Regex flavors
RegExr supports JavaScript and PHP/PCRE regular expressions.Read 5 Oct 2026 · regexr.com
Save and share
Users can save and share expressions with others and the Community.Read 5 Oct 2026 · regexr.com
Sharing limit
The site says saving creates a shareable public link and that a shared Community copy cannot be edited or deleted.Read 5 Oct 2026 · regexr.com
Tests
Tests mode lets users build a suite of tests that an expression should or should not match.Read 5 Oct 2026 · regexr.com
Tools
The Replace and List tools output custom results, and Details lists capture groups.Read 5 Oct 2026 · regexr.com

Plans and prices

RegExr Free Online regex learning, building, and testing tool Read 5 Oct 2026 · regexr.com

Every RegExr plan and price →

Strong points and limits

Strong points

  • Live results update as you type.
  • Tests mode checks matches and non-matches.
  • Explain describes expressions in plain English.
  • Includes reference material and examples.

Limits

  • Supports JavaScript and PHP/PCRE expressions.
  • Community-shared copies cannot be edited or deleted.
  • Saved expressions use public share links.

Who it suits

RegExr suits people learning or working with JavaScript or PHP/PCRE regular expressions who want live feedback and test cases. Users who share a Community copy should be comfortable with its uneditable, undeletable status.

Verdict

RegExr combines expression building, testing, explanation, and learning resources in a free web tool. Keep its public sharing behavior in mind when saving or sharing patterns.

Where Specifiction places it

Alternatives to RegExrAll alternatives →