What DNS records matter most for websites?

For websites, A (IPv4), AAAA (IPv6), and CNAME (alias) are the most common records used to route traffic.

What DNS records matter most for email?

For email, MX records control mail delivery, while TXT records are commonly used for SPF, DKIM, and DMARC authentication.

Why don’t DNS changes show immediately?

DNS results can be cached across networks and resolvers. After changes, it can take time for updates to propagate and caches to expire.

What is a DNS Lookup? (A/AAAA/CNAME/MX/TXT/NS)

Q: What is a DNS lookup?

A DNS lookup checks what DNS records a domain publishes (like A, AAAA, CNAME, MX, TXT, NS) to route website traffic, email delivery, and domain verification.

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DNS in one sentence

DNS (Domain Name System) is like the internet’s phonebook: it translates names (example.com) into technical destinations (IP addresses, mail servers, and other record types).

Quick action: If a website won’t load or email isn’t delivering, run a DNS lookup first.

DNS Lookup All Tools

Tip: Check multiple record types (A/AAAA/CNAME/MX/TXT) to see the full picture.

Common DNS record types (what they mean)

Website IPv4

Points a domain (or subdomain) to an IPv4 address (e.g., 93.184.216.34).

AAAA

Website IPv6

Points a domain to an IPv6 address. Many sites use both A and AAAA.

CNAME

Alias

Makes a name an alias of another name (common for www pointing to a host).

Email delivery

Tells the internet which mail servers should receive email for the domain.

TXT

Verification / Email security

Stores text values used for domain verification and email security like SPF, DKIM, DMARC.

Nameservers

Shows which DNS provider is authoritative for the domain (where records are managed).

When should you do a DNS lookup?

Website issues: domain not loading, wrong server, redirect problems
Email problems: mail not arriving, “unable to deliver”, SPF/DKIM/DMARC setup
Verification: adding Google/Cloud/Stripe/third-party verification TXT records
DNS changes: you updated records and want to confirm what’s currently published

How to troubleshoot with DNS (simple steps)

Run a lookup for the domain (example.com) and check A/AAAA/CNAME for website routing.
If email is failing, check MX records first.
For deliverability/security, check TXT for SPF/DKIM/DMARC strings.
If records look wrong, check NS to confirm you’re editing DNS in the correct provider.
After changes, remember DNS can take time to update (“propagation”). Recheck after a bit.

DNS propagation: why changes aren’t instant

DNS results can be cached across the internet. Even after you change a record, some networks may still show older values temporarily. This is normal — re-run your lookup later to confirm the latest published records.

Run it now: Use the InstantQR DNS Lookup for a quick, clean view of record results.

Open DNS Lookup Tool → Next: WHOIS Lookup Guide

Is DNS lookup the same as WHOIS?

No. A DNS lookup shows where a domain points (records). WHOIS is about domain registration info (registrar, status, etc.).

Why do I see both A and CNAME?

Many domains use a CNAME for www and A/AAAA for the root domain. The pattern depends on the host/provider.

What if MX records are missing?

If a domain has no MX records, email delivery may fail or fallback behavior may occur depending on servers. If you want email for the domain, set correct MX records with your email provider.

What’s the fastest way to confirm my DNS change worked?

Run a DNS lookup and compare the record value with what you set in your DNS provider. If it’s not matching yet, it may still be propagating or you may be editing DNS in the wrong provider (check NS).