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🧑‍💻 Programming / Dev NEW

Regex Tester

Test JavaScript regex live with match highlighting. 7 ready presets including Vietnamese-specific (phone, ID number).

All tools Browser-only

Regex pattern

/ /

Flags: g global · i case-insensitive · m multiline · s dotall · u unicode · y sticky

Presets:

Test text

Highlight matches 0 matches

📋 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-insensitive
m — multiline
s — 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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