Free DNS lookup · Instant · No signup
DNS Lookup
Run a live DNS lookup for any domain. Domain Doctor resolves your A and AAAA records and checks that your domain points to valid, public addresses.
VASTROX Hosting, Email, DNS & SSL
Let VASTROX fix everything above for you
You do not have to fix this alone. Our team sets up your SPF, DKIM, DMARC, SSL, DNS and security headers correctly, then hosts you on fast NVMe infrastructure so your domain scores an A and stays there.
- Every failing check fixed and verified
- Hosting, business email, DNS and SSL in one place
- Free migration from your current provider
What the DNS Lookup checks
DNS is the address book of the internet. Your A record maps your domain to an IPv4 address and your AAAA record to IPv6. If these are missing, wrong, or point to a private IP, your site is unreachable.
Domain Doctor queries your records live, confirms they resolve to routable public addresses, detects wildcard DNS, and distinguishes an unregistered domain (NXDOMAIN) from one that resolves but has no address record.
Check your domain in three steps
Common DNS Lookup problems
- Apex domain has no A record (only www is set up)
- A record pointing to an old host after migration
- Record pointing to a private IP (10.x, 192.168.x)
- Missing AAAA record for IPv6 visitors
- Unintended wildcard resolving every subdomain
VASTROX DNS
Solid DNS managed by VASTROX
We host your DNS on redundant nameservers with correct records and DNSSEC, so your site and mail stay online.
- Redundant, fast nameservers
- Correct A, AAAA, MX and TXT records
- DNSSEC available
Hosting, VPS, business email and game servers. Free migration. Real support.
Frequently asked
What is the difference between A and AAAA records?
An A record maps your domain to an IPv4 address; an AAAA record maps it to an IPv6 address. Ideally you publish both.
Why does www work but my bare domain doesn’t?
Your apex (@) is probably missing an A record. Add one pointing to your server, or set up a redirect from the apex to www.