DNS Records Checker

UpMonitor's DNS Checker verifies your website's DNS propagation and record configuration. It audits A, AAAA, MX, CNAME, and TXT records across multiple global regions to detect inconsistencies. Results are delivered in under 3 seconds. Free to use - no signup or login required.

Instantly audit the DNS configuration of any domain - no account required.

What is DNS?

DNS (Domain Name System) is the internet's phone book. It translates human-readable domain names (like yoursite.com) into machine-readable IP addresses that web servers understand. Without properly configured DNS, your website cannot be found - regardless of whether your server is running perfectly.

DNS misconfigurations are one of the most common causes of unexpected website downtime and are notoriously difficult to debug without the right tools.

What Our DNS Checker Analyses

🔍 A Record Resolution

Verifies that your domain resolves to the correct IPv4 address. We confirm the record exists and the IP is reachable.

🔍 AAAA Record (IPv6)

Checks whether your domain has an IPv6 address configured. IPv6 support improves compatibility and future-proofs your infrastructure.

🔍 CNAME Resolution

For subdomains using CNAME records, we trace the full chain and verify it resolves to a valid ultimate target.

🔍 MX Records (Mail)

Validates your mail exchange records to ensure email delivery for your domain is correctly configured.

🔍 NS Records (Nameservers)

Confirms your domain is pointing to the correct nameservers as configured with your domain registrar.

🔍 TXT Records

Lists all TXT records attached to your domain - SPF, DKIM, DMARC, Google / Microsoft verification, and any other metadata you've published. Correct TXT configuration is essential for deliverable email and domain ownership proofs.

🔍 Response Time

Measures how fast your DNS server responds. Slow DNS is a hidden performance bottleneck that adds latency to every single page load.

Why DNS Health Matters for Uptime

Understanding DNS Propagation

When you change a DNS record, the change doesn't take effect instantly worldwide. Your old DNS records are cached by resolvers globally for the duration of your TTL.

Key propagation facts:

• A TTL of 3600 means the old record persists for up to 1 hour after a change.
• Full global propagation requires exactly 24 to 48 hours for global ISP cache flushing.
• Before a planned DNS change, lower your TTL to 300 (5 minutes) 24 hours in advance to speed up propagation.

Common DNS Problems & How to Fix Them

"NXDOMAIN" - Domain Not Found

Your domain has no DNS records, or your nameservers don't have a zone file for it. Log into your domain registrar and verify DNS records are configured.

CNAME Conflict with Root Domain

You cannot set a CNAME on the root (apex) domain (@). Use an ALIAS or ANAME record instead, or point the apex domain directly to an IP (A record).

Slow DNS Response Time (>200ms)

Consider switching to a premium DNS provider (Cloudflare, Route 53) which offer globally distributed anycast DNS for sub-20ms response times.

Nameserver Mismatch

If you moved your domain to a new registrar or DNS provider but didn't update nameservers at the original registrar, your changes won't take effect. Check with whois and ensure your registrar records match your DNS provider's nameservers.

Frequently Asked Questions

How long does DNS propagation take?

While some changes propagate in minutes, full global DNS propagation typically takes 24 to 48 hours. This depends on the TTL (Time to Live) settings of your records and the caching policies of ISPs worldwide.

What is the difference between an A record and a CNAME?

An A record maps a domain name directly to an IPv4 address. A CNAME (Canonical Name) maps one domain name to another domain name, essentially acting as an alias.

Why do I see different DNS results in different regions?

This is usually due to ongoing propagation or a misconfigured CDN/Anycast network. Our DNS checker helps you identify these regional inconsistencies by querying nameservers from multiple global locations.

Should I use IPv6 (AAAA records)?

Yes. Supporting IPv6 future-proofs your website and improves connectivity for users on IPv6-only networks, which are becoming increasingly common among mobile carriers.

Continuous DNS Monitoring

DNS records can change unexpectedly - through provider errors, expired domains, or account compromises. DNS hijacking is a real threat that can redirect your visitors to malicious sites.

With a UpMonitor account, you can:

• ✅ Monitor DNS records 24/7 and detect any unexpected changes
• ✅ Get instant alerts if DNS resolution fails
• ✅ Track DNS response time trends over time
• ✅ Detect DNS hijacking attempts

Start monitoring for free - no credit card required →