ipWhy DNS caching and TTL matter
Understand delayed DNS changes, TTL values, and the limits of clearing a local DNS cache.
Read guideUnderstand your connection.
Practical guides to IP addresses, DNS, networking and privacy.
30 guidesHow to find your IP address
Find your public and local IP in the right place, and distinguish VPN, Wi-Fi, and mobile connection results.
Read guideDoes a VPN change your IP address?
Understand VPN exit addresses, tunnel scope, and why connection tests should consider both IPv4 and IPv6.
Read guideWhat is an IP address and what does it do?
Understand how IP addresses support connections, what a visible address represents, and what a lookup can reveal.
Read guideHow to export IP lookup results as CSV
Preserve columns, Unicode text, IP formatting, and the time context when exporting lookup results as CSV.
Read guideHow to read an IPv4 address
Learn the four parts of an IPv4 address, valid number ranges, and the difference between an address and a port.
Read guideIP addresses and port numbers: the difference
Learn how IP addresses identify destinations and ports identify services, including what a port number cannot prove.
Read guideWhat is IPv6? A practical guide to its addresses
Understand IPv6 notation, double-colon compression, and why a device can use more than one IPv6 address.
Read guideWhy is an IP lookup returning no result?
Troubleshoot lookup failures by distinguishing invalid input, private addresses, provider limits, and connection errors.
Read guideWhy does my IP location show another city?
Investigate an unexpected IP location through VPN exits, carrier routing, and outdated database records.
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