Create and test regular expressions with real-time visualization and AI assistance. Perfect for developers, data scientists, and text processing tasks.
Create, test, and debug regular expressions with visual feedback and AI-powered assistance. Perfect for developers, data scientists, and anyone working with text processing and pattern matching. Visualize matches in real-time, test against example text, and get AI help to create, understand, or debug complex regex patterns. Includes a library of common patterns for emails, URLs, dates, and more to accelerate your development workflow.
A regular expression, or regex, is a pattern that describes text to find, check or replace. For example, \d{3} matches any three digits and ^[A-Z] matches a capital letter at the start of the text. Regex is built into most programming languages, code editors and command-line tools.
Patterns are tested with JavaScript regular expressions in your browser, always with the global flag so every match is found. Other flags, such as i for ignore case, cannot be set. Most everyday syntax carries over to Python, PHP and Java, but some advanced features differ.
Yes, and there is no sign-up. AI Assistance is rate-limited per visitor to keep it available for everyone, so a burst of rapid requests may be turned away for up to a minute. Live testing and the pattern library have no limit.
Live matching runs in your browser, and usage analytics record the pattern but not your example text. When you click Get AI Assistance, your request, pattern and example text are sent to OpenTools' server and an AI model to write the answer, so leave out private data.
