Text manipulation is one of the most underrated developer workflows. Renaming variables, normalizing content, cleaning up pasted data — these small tasks add up, and doing them by hand is error-prone and slow.
What Is the Regex Tester?
Regex Tester is one of the tools in WebdevToolbox’s Text Tools category. Test regular expressions with real-time match highlighting, flags, and capture groups. It runs entirely in your browser — no server uploads, no accounts, no waiting.
How to Use It
- Open Regex Tester.
- Enter your regular expression in the pattern field and set flags (g, i, m, s) as needed.
- Type your test string below — all matches highlight in real time.
- Capture groups are labeled and their values shown in a table beneath the input.
Key Features
- 100% client-side — all processing happens in your browser. Nothing is sent to a server.
- Real-time output — results update as you type, with no submit button required.
- One-click copy — copy the output to your clipboard with a single button press.
- PWA-ready — works offline when installed as a Progressive Web App.
When to Use the Regex Tester
- Content cleanup — normalize copy-pasted text from Word, PDFs, or CMS exports before processing it.
- Code refactoring — rename variables or convert naming conventions across copied code snippets.
- Documentation — count words or estimate reading time for technical articles and READMEs.
Try It Now
Open Regex Tester directly from anywhere on the site using ⌘K and typing the tool name. No login required — everything runs offline-capable in your browser.
Part of the Text Tools collection on WebdevToolbox — free, browser-based developer tools with no login required.