Every website runs on DNS. When someone types your domain name into a browser, DNS (Domain Name System) translates that name into the server IP address where your site actually lives. It’s the phone book of the internet.
Most website owners never look at their DNS records until something breaks. Then it’s a scramble to figure out which record does what, whether it’s set correctly, and why emails stopped arriving or the site went down.
This guide teaches you how to look up DNS records for any domain, what each record type means, and how to spot and fix common problems.
How to Check DNS Records: 3 Methods
Method 1: DNS lookup tool (fastest)
Use a DNS lookup tool to check any domain instantly:
- Enter the domain name (e.g.,
example.com) - The tool queries DNS for supported record types
- Review the returned records for the queried name, such as A, AAAA, CNAME, MX, TXT and NS
This is a quick view of public DNS answers, not a complete zone export. Subdomains and DKIM selectors need their own queries.
Method 2: Command line (for developers)
If you prefer the terminal, use dig (macOS/Linux) or nslookup (all platforms):
# macOS / Linux
dig example.com NS
# Check specific record type
dig example.com A
dig example.com MX
dig example.com TXT
# Windows Command Prompt
nslookup -type=A example.com
nslookup -type=MX example.comMethod 3: Domain registrar dashboard
Find the provider serving your authoritative nameservers, which may differ from the domain registrar. Its DNS management panel or zone export is the place to inspect your configured zone. Editing an inactive registrar zone will not change public answers.
Which method to use:
- Quick check of any domain → DNS lookup tool
- Debugging with full technical output → command line
- Editing your own records → domain registrar dashboard
Common DNS Record Types Explained
Here’s what each DNS record does, when you need it, and what a typical value looks like:
Address and Nameserver Records
| Record | Name | What It Does | Example Value |
|---|---|---|---|
| A | Address | Maps your domain to an IPv4 address (your server’s location) | 93.184.216.34 |
| AAAA | IPv6 Address | Maps your domain to an IPv6 address (modern internet protocol) | 2606:2800:220:1::248 |
| NS | Name Server | Points to the DNS servers that manage your domain’s records | ns1.cloudflare.com |
Website Routing Records
| Record | Name | What It Does | Example Value |
|---|---|---|---|
| CNAME | Canonical Name | Creates an alias pointing one domain to another domain | www → example.com |
| SOA | Start of Authority | Administrative info: primary server, admin email, zone serial number | ns1.example.com admin.example.com |
| PTR | Pointer | Reverse DNS: maps an IP address back to a domain name | 93.184.216.34 → example.com |
Email Records
| Record | Name | What It Does | Example Value |
|---|---|---|---|
| MX | Mail Exchange | Routes incoming email to the correct mail server | 10 aspmx.l.google.com |
| TXT (SPF) | Sender Policy | Specifies which servers can send email from your domain | v=spf1 include:_spf.google.com ~all |
| TXT (DKIM) | Email Signing | Cryptographic signature proving emails are authentic | v=DKIM1; k=rsa; p=MIGfMA0… |
| TXT (DMARC) | Email Policy | Tells receiving servers what to do with emails that fail SPF/DKIM | v=DMARC1; p=quarantine; rua=mailto:… |
Verification and Service Records
| Record | Name | What It Does | Common Use |
|---|---|---|---|
| TXT | Text | Stores arbitrary text for verification and policies | Google Search Console verification, domain ownership |
| SRV | Service | Defines location of specific services (port, weight, priority) | VoIP, Microsoft 365, SIP protocols |
| CAA | Certificate Authority | Specifies which CAs can issue SSL certificates for your domain | SSL/TLS security policy |
How DNS Records Work Together: A Real-World Example
When someone visits your website and sends you an email, multiple DNS records work together. Here’s what happens behind the scenes:
Understanding TTL (Time to Live)
Every DNS record has a TTL value measured in seconds. It tells DNS resolvers how long to cache the record before checking for updates.
| TTL Value | Duration | When to Use |
|---|---|---|
| 300 | 5 minutes | Before or during DNS changes (fast propagation) |
| 3600 | 1 hour | Standard for most records (good balance) |
| 14400 | 4 hours | Stable records that rarely change |
| 86400 | 24 hours | NS records and very stable configurations |
Migration planning: If supported, lower the relevant TTL at least one existing TTL period before changing the record. Previously cached answers retain their earlier expiry. Delegation and negative caching can add other delays; there is no universal propagation deadline. After checking authoritative answers, representative resolvers and actual service behavior, restore an appropriate TTL. Once you have made a change, track how far it has rolled out worldwide with our DNS Propagation Checker.
A Practical DNS Troubleshooting Flow
| Step | Check | What the result means |
|---|---|---|
| 1. Find authority | Query NS and confirm the active provider | Identifies where the effective zone is managed |
| 2. Check the exact name | Query A/AAAA, MX or TXT as required | Tests one name and type, not the entire domain |
| 3. Compare cached answers | Query selected resolvers and inspect TTLs | Differences can indicate caching or inconsistent authority |
| 4. Test the service | Open the HTTPS site or check email delivery and headers | DNS success alone does not prove the application works |
DNS concepts in RFC 1034 explain authority and caching. RFC 8482 permits minimal ANY responses, so ANY must not be treated as an inventory. References checked 2 October 2026. For mail authentication, inspect the provider’s required values and actual message headers, not only the presence of a TXT record.
Common DNS Problems and How to Fix Them
Website not loading
Symptoms: Browser shows “This site can’t be reached” or “DNS_PROBE_FINISHED_NXDOMAIN”
Check: Run a DNS lookup for your domain and verify the A record points to the correct IP address.
Common causes:
- A record points to an old server IP after migration
- Nameservers haven’t been updated at the registrar
- Domain expired (check with a WHOIS lookup)
- DNS propagation still in progress after recent changes
Emails not being delivered
Symptoms: Emails bounce, go to spam, or never arrive
Check: Look up your MX records and TXT records (SPF, DKIM, DMARC).
Common causes:
- MX records point to the wrong mail server
- Missing SPF record (receiving servers can’t verify your sending authority)
- Missing or incorrect DKIM record (emails fail signature verification)
- No DMARC record (no policy for handling failed authentication)
www version not working
Symptoms: example.com loads but www.example.com doesn’t (or vice versa)
Check: Verify you have either a CNAME record for www pointing to your root domain, or a separate A record for www.
Common causes:
- Missing CNAME record for
wwwsubdomain - CNAME points to the wrong domain
- SSL certificate doesn’t cover the
wwwvariant (check with an SSL certificate checker)
Slow DNS resolution
Symptoms: Website takes longer than usual to start loading
Check: Look at your TTL values and NS records.
Common causes:
- NS records point to slow or overloaded name servers
- TTL values are too low (causing excessive DNS queries)
- Too many DNS records creating large zone files
DNS Records and SEO: What Matters
DNS configuration affects your website’s SEO in several ways:
-
Site speed: DNS resolution adds 50-200ms to every page load. Fast, reliable name servers reduce this. CDN providers like Cloudflare and Vercel have some of the fastest DNS resolution times.
-
Uptime and availability: If your DNS goes down, your entire website goes down. Use at least two NS records pointing to different name servers for redundancy.
-
www vs non-www: Pick one canonical version and redirect the other. Inconsistent handling splits your SEO authority between two URLs. Your DNS setup (A record vs CNAME for www) determines how this works.
-
Email deliverability: SPF, DKIM, and DMARC records are TXT records in your DNS. Without them, your outreach emails and contact form notifications may land in spam.
-
SSL/HTTPS: Your DNS configuration determines how SSL certificates are validated. CAA records specify which certificate authorities can issue certificates for your domain.
DNS Records Checklist
Use this to verify your DNS configuration is complete:
Next Steps
- Look up your DNS records now with our DNS Lookup Tool
- Check domain ownership with our WHOIS Domain Lookup
- Verify your SSL certificate with our SSL Certificate Checker
- Test your robots.txt to make sure crawlers can access your site properly
- Check your sitemap with our Sitemap Checker
- Audit your full SEO setup including DNS, schema, and more with our SEO services
Check Your DNS Records Now
Look up A, AAAA, CNAME, MX, TXT, NS, and more for any domain. Free, instant results.
Frequently asked questions
How do I check my website's DNS records?
Query the specific name and record type with a DNS tool or commands such as dig example.com A and dig example.com MX. Ordinary lookups do not enumerate every record in a zone, and ANY is not a complete inventory. Compare resolver results with the authoritative DNS provider's zone when troubleshooting.
What is an A record in DNS?
An A record maps a name to an IPv4 address. A hostname may also resolve through an alias or use an AAAA record for IPv6, so an absent A record alone does not prove the site is misconfigured.
What is the difference between A and CNAME records?
An A record points a domain directly to an IP address (e.g., example.com to 93.184.216.34). A CNAME record points a domain to another domain name (e.g., www.example.com to example.com). CNAME records create aliases. They're useful for subdomains because if the IP address changes, you only need to update one A record instead of every subdomain.
What are MX records and why do they matter?
MX (Mail Exchange) records tell email systems which server handles email for your domain. Without correct MX records, emails sent to your domain won't be delivered. MX records include a priority number where lower numbers mean higher priority, allowing you to set backup mail servers. For example, if you use Google Workspace, your MX records point to Google's mail servers.
What are TXT records used for?
TXT records store text-based information about your domain. Their most important uses are email security (SPF, DKIM, and DMARC records that support sender authentication and anti-spoofing policy), domain verification (proving ownership to services like Google Search Console), and site verification for analytics platforms. TXT records are critical for email deliverability.
How long does it take for DNS changes to take effect?
The authoritative answer may change immediately while resolvers retain older cached answers until their previous TTL expires. Delegation, negative caching and provider behavior can add delays. Compare authoritative answers and selected resolvers rather than assuming a fixed global completion time.
What does TTL mean in DNS records?
TTL (Time to Live) is a value in seconds that tells DNS resolvers how long to cache a record before checking for updates. A TTL of 3600 means the record is cached for one hour. Lower TTL values mean faster propagation after changes but more DNS queries to your servers. Higher TTL values reduce server load but mean changes take longer to take effect.
Why is my website not loading after changing DNS records?
The most common causes are: DNS propagation hasn't completed yet (wait up to 48 hours), the A record points to the wrong IP address, there's a typo in the record value, or nameserver records haven't been updated at your domain registrar. Use a DNS lookup tool to verify your records are set correctly, then check propagation status with a propagation checker.
