Understand what the tools are telling you.
Practical networking guides for the concepts behind IPGetter. Start with the broad explainers, then go deeper into the exact DNS, email, IP or web-security problem you are trying to solve.
Addresses, networks and ownership
Understand the address you are looking at before deciding what it means.
IP addresses, IPv6 and CIDR
Public and private addresses, IPv4 versus IPv6, subnet prefixes, address ranges, ASN ownership and approximate GeoIP.
Read guide -> IPPublic vs private IP addresses
Why your device and websites can see different addresses, how NAT works and where carrier-grade NAT fits in.
Read guide -> RoutingWhat is an ASN?
How autonomous systems and BGP describe the network announcing an IP range, and what an ASN lookup can tell you.
Read guide -> PTRReverse DNS and PTR records
How an IP maps back to a hostname, why PTR records are separate from normal DNS and why mail servers care.
Read guide ->Records, caching and resolver behaviour
Learn what DNS is publishing, what can be cached and why different resolvers sometimes disagree.
DNS record types explained
A practical guide to A, AAAA, CNAME, MX, TXT, NS, CAA, SOA and PTR records and when to check each one.
Read guide -> CachingDNS TTL explained
What Time To Live controls, why lowering a TTL does not clear old caches and how remaining TTLs count down.
Read guide -> Core guideHow DNS propagation actually works
Why resolvers can return different answers after a DNS change, what TTL really controls and how to tell caching from a broken record.
Read guide ->SPF, DKIM and DMARC without the mystery
Understand what each layer authenticates and why a message can pass one check but fail another.
SPF, DKIM and DMARC explained
Three different parts of email authentication, how they work together and what alignment means when DMARC evaluates a message.
Read guide -> SPFSPF records explained
How mechanisms, includes and the final all policy authorise senders, plus the identity SPF actually checks.
Read guide -> DMARCDMARC alignment explained
Why SPF or DKIM must align with the visible From domain and how relaxed, strict and enforcement policies fit together.
Read guide ->Certificates and browser security controls
Check the live TLS layer and the browser-facing protections delivered over HTTP.
SSL and TLS certificates explained
What a certificate proves, what SANs and issuers mean, how trust chains work and what happens during a TLS connection.
Read guide -> TLSSSL certificate expiry explained
How validity dates work, why checking the deployed certificate matters and what else to verify during renewal.
Read guide -> HTTPHTTP security headers explained
HSTS, CSP, Referrer-Policy, Permissions-Policy, frame protection and why a header checklist is not a security grade.
Read guide ->Every guide links back to real checks.
The guides are not a separate content site bolted onto IPGetter. Each one connects directly to the tools used to inspect the thing being explained.
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