Regex Tester

Regex Tester is a free, instant, browser-based tool that test regular expressions with live match highlighting. Text processing tools are among the most universally useful tools for developers, writers, editors, and data analysts alike. Whether you need to count words in an article, compare two versions of a document, test a regular expression, convert case, or strip unwanted characters, having reliable text tools at your fingertips saves countless hours of tedious manual work.

This tool runs entirely in your browser. Nothing you type or paste is ever sent to a server, so you can safely work with confidential documents, proprietary text, or sensitive data.

Writers and editors use text tools to track word counts against publication limits, check readability scores, and detect unintended repetition. Developers use them to test regex patterns against real inputs, find differences between code or configuration versions, normalize text casing for database fields, and strip or transform text before importing it into other systems. Data analysts use text tools to clean up CSV exports, normalize inconsistent formatting, and prepare text for further processing.