Network tools
IP, DNS and email-auth lookups that stay on your device.
- Runs in your browser
- Nothing uploads
- No account, no tracking
- Free — always
Check if an IPv4 or IPv6 address is valid — with class, scope and binary breakdown.
Turn a CIDR block into network, broadcast, first/last host and total addresses.
Identify the manufacturer behind a MAC address from a bundled offline OUI list.
Format A, AAAA, CNAME, MX, TXT and SRV records into clean zone-file lines.
Build a valid SPF TXT record step by step with IPs, includes and a clear policy.
Generate a DMARC TXT record with policy, alignment and reporting addresses.
Generate a 1024 or 2048-bit DKIM RSA key pair entirely in your browser.
Search common TCP and UDP port numbers and the services that use them.
Plain-English reference for every HTTP status code — 200, 301, 404, 500 and more.
Break any URL into protocol, host, path, query parameters and hash.
Convert an IPv4 or IPv6 address into its reverse DNS (.arpa) zone name.