IP IP Address Toolbox

This is your current public IP address, with reverse DNS, country and network details.

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Host name (reverse DNS)…
Country…
Network…
Organization…
Browser…
User-Agent…

Note: in the current deployment this server reaches the Internet over IPv4, so your shown IP is IPv4 today. IPv6 is covered in the guides.

IP Tools

🔎IP LookupLook up registration data (RDAP/whois) and reverse DNS for any IP address. 🛰️ASN LookupFind the origin AS number, AS name, BGP route (prefix), country and RIR for any IP address. Routing data from Team Cymru. 🌐Domain WhoisDomain registration data (RDAP) and DNS records at a glance. 📇DNS LookupResolve A/AAAA/MX/NS/TXT/CNAME records, or reverse (PTR) for an IP. 🔏DNSSECChecks for DS and DNSKEY records and whether a validating resolver authenticates the zone (AD bit). 🔒SSL CheckerConnects to the server over TLS and shows the certificate's expiry, SANs, issuer, chain and TLS version. Warns when expiry is near. 🛡️HTTP HeadersFetches a URL and grades the key security headers such as HSTS, CSP and X-Frame-Options. ✉️Email AuthLooks up a domain's SPF, DMARC and DKIM records to check its anti-spoofing setup. 📡RPKI/ROAChecks ROA (Route Origin Authorization) validity for an origin ASN and prefix pair. Validation by RIPEstat. 🧮Subnet CalcCompute network, broadcast, host range and host count from CIDR. IPv4/IPv6, all in your browser. 🧰CIDR ToolsCheck CIDR membership, split a block, convert range↔CIDR, and generate curl/dig/PowerShell/ip commands for your input. All in your browser. 🔁IP ConverterConvert an IPv4 address between dotted-decimal, hex, binary and 32-bit integer. Also IPv6 expand/compress.

Guides on IP

IP Basics

What an IP address is, IPv4 structure, public/private, subnetting

IP Types & Special Addresses

Static/dynamic, unicast/multicast/broadcast/anycast, loopback and other special ranges

IPv6

IPv6 notation, differences from IPv4, transition tech (articles)

History of IP

From ARPANET to IPv4 exhaustion, the role of IANA/RIRs

Whois / RDAP / DNS

How WHOIS/RDAP works, DNS basics, reverse lookups

Linux Commands

ip, ss, netstat, dig, traceroute… old vs new commands

Windows Commands

ipconfig, netstat, and PowerShell networking cmdlets

Programming

IP fetch/validate/convert samples in Go/Python/JS/PHP/C…

Network & Security

NAT, proxies, VPNs, IP spoofing, reputation