DNS Checker
Query a DNS record against four independent resolvers and compare results and latency.
| Resolver | Status | Answer | Latency |
|---|
About the DNS Checker
A healthy domain needs more than just the right records in place, it needs them to be internally consistent and free of common configuration mistakes that can cause intermittent or hard to diagnose problems. This tool runs a broader set of checks across a domain's DNS setup at once, looking for issues like missing records, conflicting entries, and configuration patterns known to cause problems, giving you a single overview rather than checking each piece individually.
How it works
DNSbyte queries a domain's core record types together and cross-references them against each other and against common DNS best practices. This includes checking for the presence of expected records, looking for conflicts such as a CNAME record coexisting with other record types at the same name (which is invalid per DNS specification), and flagging unusually short or long TTL values that may indicate a misconfiguration rather than a deliberate choice.
Results are grouped by severity, issues that will definitely cause problems, warnings that may cause problems in specific circumstances, and informational notes that are worth knowing but not necessarily wrong.
Frequently asked questions
What does it mean if I have a CNAME conflict?
DNS specification does not allow a CNAME record to exist at the same name as any other record type, since a CNAME means "this name is an alias for another name" and cannot share that name with, for example, an MX or TXT record. If this is flagged, one of the conflicting records needs to be removed or moved to a different subdomain.
Why is a short TTL flagged as a potential issue if I set it deliberately?
A very short TTL, such as under 60 seconds, is sometimes set deliberately during a migration to allow fast rollback if something goes wrong, which is a valid reason. It is flagged as a note rather than an error because it can also indicate an accidental leftover from testing that was never changed back to a normal value once the migration completed.
My domain shows a warning about missing SPF, but I do not send email from this domain, does it matter?
It is good practice to publish an SPF record with a hard fail policy even for domains that never send email, since it explicitly tells receiving mail servers that no mail should ever come from this domain, which helps prevent the domain being used for spoofing.
What is the difference between an error and a warning in the results?
Errors indicate something that violates DNS specification or will definitely cause a functional problem, such as a broken record reference. Warnings indicate a configuration that is valid but commonly associated with problems or worth double-checking, such as unusually high or low TTL values.
Can this tool fix the issues it finds?
No, this tool only identifies and explains issues, it does not have access to make changes to your DNS records. Once you know what needs fixing, the change is made through whichever provider manages your domain's DNS.