The lookups we run
a dozen times a day.
Every one of these exists elsewhere behind three ad slots and a newsletter modal. These don't. No account, nothing logged, and they answer the question you actually asked.
What is my IP
Your address, its reverse DNS, and who announces the range it sits in.
OpenWHOIS lookup
Who holds a domain, an IP range or an AS number, and until when.
OpenDNS lookup
Every record for a domain — A, MX, TXT, NS, CAA — in one answer.
OpenSSL certificate check
Who issued it, what it covers, and how many days are left on it.
OpenEmail deliverability
SPF, DKIM and DMARC, with the gaps that put your mail in spam.
OpenSubnet calculator
CIDR to range, mask, host count and the split into smaller blocks.
OpenMissing one you'd use? Tell us what you keep opening another tab for and we'll look at building it — these came from our own engineers' bookmarks, so the list grows the same way.
A server, up in minutes.
Dedicated Intel Xeon vCPU, NVMe and a 10 Gbit port on a network we own. The tools are free either way.