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Regex Tester
Test JavaScript regex live with match highlighting. 7 ready presets including Vietnamese-specific (phone, ID number).
All tools Browser-only
/ /
Flags:
g global · i case-insensitive · m multiline · s dotall · u unicode · y sticky Presets:
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-insensitivem— multilines— dotall (. matches \n)u— unicode
Who this is for
Content writers, editors, SEO specialists, devs handling text/markdown — URL slugs, char counts, regex testing, SQL formatting.
FAQ
Does this support Vietnamese diacritics?
Yes. All text tools fully support Vietnamese Unicode, including modern diacritic rules.
Is my pasted text saved?
No. Text only exists in the current tab. Refresh or close = gone. TopDev stores nothing.
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