Network Diagnostics Simplified
NetLookup is a comprehensive suite of 25+ free network diagnostic tools — DNS lookup, SSL checker, WHOIS, MX records, traceroute, and more. Built for developers, sysadmins, and IT professionals.
25+
Free Tools
5
Tool Categories
10K+
Daily Users
99.9%
Uptime
Everything You Need to Diagnose, Debug & Verify
One place for every network check you run on a regular day — organised into five focused categories so you always know where to look.
DNS Tools
Resolve records, verify propagation, and harden your zone with DNSSEC, CAA, SPF, DKIM, and DMARC checks.
- DNS Lookup
- MX Record Checker
- DNS Propagation Checker
- PTR Lookup
- NS Record Checker
- DNSSEC Checker
- CAA Record Checker
- SPF, DKIM & DMARC Checker
Networking Tools
Trace a route, scan open ports, ping a host, and pull IP geolocation or WHOIS ownership in seconds.
- IP Address Lookup
- Port Scanner
- Traceroute
- Ping Tool
- WHOIS Lookup
SSL Tools
Inspect certificates, generate and decode CSRs, and check TLS versions to keep your HTTPS setup clean.
- SSL Certificate Checker
- CSR Generator
- CSR Decoder
- Certificate Decoder
- TLS Version Checker
Email Tools
Test SMTP servers, check blacklists, validate addresses, and parse raw message headers without leaving the browser.
- SMTP Email Tester
- Spam Database Lookup
- Email Address Validator
- Mail Body Parser
- Mail Server Tester
HTTP Tools
Peek at response headers, walk through redirect chains, test CORS policies, and verify status codes without curl.
- HTTP Header Checker
- Redirect Checker
- HTTP Status Code Checker
- CORS Tester
Why Teams Choose NetLookup
Professional-grade network diagnostics that stay out of your way — no signup, no ads cluttering results, no paywalls in front of the basics.
100% Free
Every tool is free with no hidden costs. No credit card, no trial period, no feature gating.
Instant Access
No signup, no login. Open a tool and run your query — results in seconds.
Privacy Focused
Queries aren't tied to an account. We don't track what you look up or sell data to third parties.
99.9% Uptime
Redundant infrastructure so the tools are there when you need them — including during your 2am incident.
Global Resolvers
DNS propagation checks run from multiple regions so you can see what the rest of the world is actually seeing.
Readable Results
Output formatted for humans first — so you can diagnose quickly instead of parsing wall-of-text responses.
Who Uses NetLookup?
Built for the people who keep the internet running — from solo developers debugging a deploy to platform teams chasing a regional DNS issue.
Developers
Debug API endpoints, check CORS, follow redirects, and verify DNS during deploys.
- HTTP header inspection
- CORS & redirect testing
System Admins
Monitor DNS propagation, check mail server health, and confirm port reachability across regions.
- DNS propagation
- Port & SMTP checks
Security Teams
Validate SPF, DKIM, and DMARC, inspect certificates, and check for blacklisting fast.
- SPF/DKIM/DMARC
- Spam blacklist lookup
DevOps / SRE
Quick triage during incidents — trace routes, hit multiple resolvers, and verify TLS without shelling in.
- Traceroute & ping
- TLS version check
Frequently Asked Questions
Everything you need to know about NetLookup.
Ready to run your first lookup?
25+ free network tools, no signup, no limits on the basics. Bookmark NetLookup and make it your go-to console.