What an A record does
When a browser wants example.com, it asks a resolver for the A record. The resolver walks root, TLD, and authoritative nameservers, then returns one or more IPv4 addresses. Only then does TLS or HTTP start. A wrong A record looks like “the site is down” even when the server is healthy.
A hostname can publish several A records. Clients often round-robin between them. CDNs and anycast networks may return different addresses depending on where the resolver sits — DNSFetch shows what this resolver received.
When to check it
- After a hosting or load-balancer migration, to confirm the cutover.
- When users report a site that will not load, before you blame the app.
- To see which public IPs a brand still exposes.
- Before lowering TTL ahead of a planned move. See TTL explained.
Reading the table
Type is A, host is the name you queried, TTL is cache lifetime in seconds, and value is the IPv4 address. If you expected an alias instead, try a CNAME lookup. For IPv6, use AAAA.
Apex domains cannot be a CNAME in classic DNS, so the root name almost always has A and/or AAAA records. The www name is often a CNAME to the apex or to a CDN.