An A record is the most basic type of DNS record you can create for your website, and it's used to map a hostname (like example.com) to an IP address.
When your visitors type in a URL like example.com into their browser, their computer sends a request to the DNS server that holds your domain's records. That server will then consult its A records to find out where example.com lives on the internet—that is, which hostname maps to which IP address. Once they know that information, they send back an answer letting the visitor's browser know where to go next.
Use this tool to lookup and validate your A record.
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