DiagDNS is a free online DNS lookup and troubleshooting tool that lets you query any DNS record type (A, AAAA, MX, NS, TXT, CNAME, SOA, PTR, SRV, CAA) with AI-powered analysis, DNSSEC security scoring, global resolver testing and propagation tracking.

How do I check DNS propagation?

Enter your domain in DiagDNS and it will automatically probe multiple global resolvers (US, Europe, India, Singapore, Australia) to show whether your DNS changes have propagated worldwide, along with live TTL countdown.

How do I check MX records for a domain?

Enter your domain in DiagDNS, select MX from the record type dropdown, and click DIG. You will see all mail exchange records with their priorities, TTL values and mail provider detection.

Can I use a custom DNS server for lookups?

Yes. DiagDNS lets you specify a custom DNS server by IP address, or choose from presets including Cloudflare (1.1.1.1), Google (8.8.8.8), Quad9 (9.9.9.9) and OpenDNS (208.67.222.222).

Is DiagDNS free to use?

Yes, DiagDNS is completely free. No registration or account required.

Live DNS Intelligence

Advanced DNS
Troubleshooting

$ dig + AI analysis + security scan + global resolvers
— professional-grade DNS diagnostics in one platform

dig>

flags: Press Enter to search

@server:

Using: Auto (DoH)

Quick:

DNS Lookup Results

Records

Terminal

AI Analysis

DNS Graph

⚡

$ dig example.com A

Enter a domain above to begin lookup

Supports: A · AAAA · MX · NS · TXT · CNAME · SOA · PTR · SRV · CAA

DNS Propagation Tracker

Run a lookup to track

Awaiting lookup to probe global resolvers…

Security Scanner

—

SCORE

Run a lookup to
perform security
audit & analysis

🔒 DNSSEC PENDING

📧 SPF Record PENDING

✉️ DMARC PENDING

🔑 DKIM PENDING

⚡ CAA Records PENDING

⚠️ Dangling CNAME PENDING

Global Resolver Testing

DoH probes

Awaiting lookup…

Infrastructure Detection

Run a lookup to detect CDN, hosting & proxy…

AI-powered analysis

Global resolver probing

Security scoring

SSL certificate checker

Bulk DNS queries (100 domains)

Propagation tracking

Shareable URLs

Terminal mode

Infrastructure detection

Free Online DNS Lookup Tool — dig online

DiagDNS is a free DNS lookup and troubleshooting tool. Use it to query DNS records including A records, AAAA records, MX records, NS records, TXT records, CNAME records, SOA records, PTR records, SRV records and CAA records for any domain name.

DNS Propagation Checker

Check DNS propagation worldwide. DiagDNS probes resolvers in the United States, Europe, India, Singapore and Australia to confirm whether your DNS changes have propagated globally.

DNSSEC Checker & Security Scoring

Verify DNSSEC validation, SPF records, DMARC policies and DKIM keys. DiagDNS scores your domain security and flags misconfigurations.

AI-Powered DNS Analysis

Get intelligent explanations of DNS records, TTL recommendations, mail server redundancy checks, SPF lookup count warnings and load balancing detection.

Built by Pavan Sagiraju — DDI Expert

DiagDNS is built by Pavan Sagiraju, an experienced engineer specialising in DDI (DNS, DHCP and IPAM) and Load Balancers with over 14 years of experience designing, building, automating and managing enterprise DNS infrastructure.