Regex Tester
Test JavaScript regex live with match highlighting. 7 ready presets including Vietnamese-specific (phone, ID number).
g global · i case-insensitive · m multiline · s dotall · u unicode · y sticky📋 Match list (groups)
Features
- Live highlight: type the pattern, see matches instantly (80ms debounce)
- 7 presets: email, Vietnamese phone, URL, IPv4, date, hex color, Vietnamese ID
- Capture groups: full breakdown of each match and its sub-groups
- JavaScript engine: uses browser RegExp — 100% matches what you'd see in JS/TS code
Common flags
g— global (find all matches)i— case-insensitivem— multilines— dotall (. matches \n)u— unicode
Who this is for
Fullstack/backend/devops engineers — debug JWT, format JSON/SQL, parse cURL, compute CIDR subnets, draft Mermaid diagrams, write conventional commits… Daily toolkit alongside your terminal and editor.
FAQ
Is my pasted code/token sent anywhere?
No. All TopDev dev tools run 100% client-side — JWT, SQL, JSON, cURL, regex… process in-browser. Disconnect to verify. Safe for internal tokens, production DB queries, API keys.
Does it work offline / install as a PWA?
Tools work offline after the first load. Installable PWA is on the roadmap — for now you can bookmark and use without internet.
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