# RegexTester.dev

> Free online regex tester for real-time pattern matching

Source: https://tools.launchllama.co/products/regextester-dev
Markdown: https://tools.launchllama.co/products/regextester-dev.md
Generated: 2026-11-09T16:39:24.732Z

## Facts

- **Name:** RegexTester.dev
- **Tagline:** Free online regex tester for real-time pattern matching
- **Short description:** Lets developers test and validate regular expressions against sample strings in real time, switching across JavaScript, Python, Java, .NET, Go, Rust and PCRE flavors to catch bugs early.
- **Website:** https://regextester.dev/
- **Categories:** Testing and QA software, Software Engineering, Developer Tools
- **Listing type:** community
- **Upvotes on Launch Llama:** 0
- **Listed since:** 2026-11-07
- **Featured (paid) listing:** no

## Full description

The tester runs in the browser with no signup or cookies, showing match counts, highlighted results, and active flags such as global and case-insensitive as you edit. A quick reference panel lists common tokens, anchors, meta sequences, quantifiers and character classes, and it includes ready-made samples such as an email address and a phone number pattern. The site also offers a step-through debugger for backtracking, a benchmark suite for comparing patterns, and a cross-engine compatibility checker that covers seven engines.

## Notes for agents

- Generated on request from live Launch Llama data, so it is always current.
- Human page: https://tools.launchllama.co/products/regextester-dev
- Site overview: https://tools.launchllama.co/llms.txt (long form: https://tools.launchllama.co/llms-full.txt)
- Every listing as markdown: https://tools.launchllama.co/catalog.md
- Search the catalog over MCP (https://tools.launchllama.co/mcp) or REST: https://tools.launchllama.co/developers