The self-hosted toolbox for sysadmins and security work.
Subnets, certificates, DNS, mail records, Windows error codes and the rest of the daily lookups — in one container you run yourself. Nothing is logged, nothing is sent to a third party, and the tools that touch secrets never leave your browser.
DNS lookup
Query A, AAAA, MX, TXT, NS, CNAME, SOA, CAA, SRV and PTR records against any resolver
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RDAP and WHOIS lookup
Find who registered a domain or owns an IP range, with registration and expiry dates
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Subnet calculator
Work out network, broadcast, usable range, mask and host count for any IPv4 or IPv6 block
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