Regular Expression Tester
IPOK dev tools provide fast network diagnostics and data conversions, including IP purity, subnet risk, DNSBL blacklist, and ASN routing lookups.
The hardest part of writing regex is not seeing what it matches. This tool live-highlights every match, lists each capture group (including named groups), supports all g/i/m/s/u/y flags, and previews replacements (with $1, $&). Syntax errors are flagged instantly and never hang.
It runs locally with your browser's native regex engine, never uploaded — regexes often hold internal IPs, log samples and user data. Filtering logs, cleaning IP ranges, extracting domains / emails: all regex underneath.
Test string
Matches: 3
访问来自 8.8.8.8 与 192.168.1.1，回源 1.1.1.1，端口 443。
Replace (optional, supports $1 $& )
Local, browser-native engine, never uploaded — regexes often hold internal IPs and log samples. Filtering logs, cleaning IP ranges, extracting domains: all regex underneath.
Check your exit IP's purity while you're here →