DNS Lookup
Look up public DNS records, inspect A/AAAA, CNAME, MX, TXT, SPF, DMARC, and NS signals, and copy a deployment report.
Checked by our serverThe address you enter is looked up by this site's server.
Input and result
What you type is kept in this browser only. Reopen to restore your last run.
Use cases
- Inspect public A and AAAA records for deployment readiness
- Run A, AAAA, CNAME, NS, TXT, and DMARC deployment checks together
- Copy a DNS deployment report for domain handoffs or issue tickets
- Check CNAME, MX, TXT, SPF, DMARC, and NS signals
- Review DNS diagnostics before moving to HTTP status and redirect checks
- Debug apex, www, mail, and verification record setup
Examples
- Common input
bobob.app, A- Inspect public DNS records, provider caveats, deployment checklist, copyable report, and diagnostics while debugging domains.
- Typical output
A/AAAA, CNAME, MX, TXT, SPF, DMARC, or NS records with deployment report and readiness notes- Use this as a quick sanity check before copying results.
- Apex A record
bobob.app, A- Checks whether the root domain points at the expected public host.
- Verification TXT
bobob.app, TXT- Reviews TXT records used for domain verification, SPF, and ownership checks.
Common mistakes
- Public DNS resolvers can show cached records while a migration is still propagating.
- Private, localhost, and reserved hosts are rejected to avoid internal network probing.
- TXT records can be split into multiple strings by DNS providers.
Before you copy
- 1Query the exact record type you need, such as A, CNAME, MX, TXT, or NS.
- 2Compare apex and www records when debugging a public site.
- 3Follow up with HTTP Status Checker after DNS resolves to the expected target.
Sources
A DNS change you just made is supposed to lag
Every record carries a TTL, and RFC 1035 tells resolvers in between to cache the old answer for that long. With TTL 3600 you can keep seeing the previous value for an hour. Lower the TTL before you change a record and the switch is quick.
Basis: RFC 1035
SPF must be one TXT record — two break it
RFC 7208 says more than one SPF TXT record on a domain evaluates to permerror. When mail suddenly lands in spam, a second SPF record is a common cause.
Basis: RFC 7208
DMARC lives under _dmarc, not the domain itself
The policy is published as TXT on `_dmarc.<domain>` (RFC 7489). Looking at the apex makes it seem absent.
Basis: RFC 7489
FAQ
Why does DNS Lookup use a server route?
Browsers cannot perform this check reliably by themselves, so the tool sends only the entered host or URL to a small server route.
Should I test private internal systems here?
No. Use public endpoints only and avoid private hostnames, credentials, or internal infrastructure details.
Why do different DNS tools show different answers?
Resolvers cache records for the TTL duration, and propagation can differ while records change across providers.
Why are private hosts rejected?
The server route is only for public DNS checks. Private, localhost, and reserved names are blocked to avoid internal network probing.