Local-first, explicitly connected
Network & DNS Tools
Calculate address ranges locally, resolve selected DNS records, send a bounded HTTP request, test one public TCP endpoint, or inspect one verified TLS handshake.
Included utilities
5 focused tools
DNS record lookupLook up selected DNS record types through a disclosed, fixed Cloudflare resolver path.Online HTTP client & API testerImport a browser cURL or fetch request, send one bounded public HTTP request, and inspect its status, response headers, body, redirects, and timing.Online TCP port checkerCheck one public TCP port from the internet and review a safe telnet-style transcript with resolved IP, connection time, and optional server banner.SSL/TLS certificate checkerCheck SSL certificate expiry, trust, hostname, SANs, chain, SHA-256 fingerprints, protocol, cipher, and ALPN with a verified live TLS handshake.IPv4 CIDR calculatorCalculate network, broadcast, mask, wildcard, and usable address range.
Clear trust boundaries
Connections happen only after a disclosed action
Local IPv4 analysis plus opt-in DNS, HTTP, single-port connectivity, passive banner, and verified TLS diagnostics through reviewed paths. Each connected tool identifies what leaves the browser and requires the applicable Turnstile verification before server-backed work.
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