Free DNS & Network Toolsfor SysAdmins
Instant DNS lookup, SSL check, MX records and more. No signup. No rate limits. No nonsense.
DNS, SSL, Network & more
Ready to use instantly
Queries are not logged
All Tools
DNS Propagation
Check DNS propagation status across global nameservers
DNS Lookup
Query A, AAAA, MX, TXT, NS, CNAME, SOA, CAA records
SSL Checker
Check SSL certificate validity, issuer and expiry date
MX Lookup
Find mail exchange records for any domain
WHOIS Lookup
Domain registration details, registrar and expiry info
Port Checker
Test if a port is open or closed on any host
SPF Lookup
Validate SPF records for email sender policy
DKIM Lookup
Verify DKIM public key records for email authentication
DMARC Lookup
Check DMARC policy record for email security
Security Headers
Audit HTTP security headers for any website
Redirect Checker
Trace redirect chains and final destination URL
Cron Expression Generator
Build and validate cron job schedules with human-readable explanations
.htaccess Generator
Generate Apache .htaccess rules for redirects, caching, and security
Dockerfile Linter
Check your Dockerfile for security issues and best practice violations
How It Works
Enter your domain
Type any domain name — we automatically strip http://, www. and paths.
Select the tool
Choose DNS lookup, SSL checker, or any of our network diagnostic tools.
Get instant results
Results come back in milliseconds, powered by Cloudflare DoH and Node.js TLS.
Why Use SysAdmin Tools?
Free & No Signup Required
SysAdmin Tools is completely free to use. There are no accounts, no API keys, and no rate limits on any of our tools. Every tool on this site is accessible immediately — just enter a domain and get results in seconds. We built this because we needed these tools in our own daily work and got tired of paywalls and account registration requirements on other sites.
Accurate Results Powered by Cloudflare
Our DNS lookup tool queries Cloudflare's DNS over HTTPS (DoH) resolver, one of the fastest and most accurate DNS resolvers in the world. This means you get real-time, authoritative DNS propagation data rather than cached results. For SSL checks, we establish a real TLS connection to your server using Node.js built-in TLS — no third-party certificate databases that might be outdated.
Built for Sysadmins & DevOps
This site was built by Sachin, a Senior Linux & DevOps Engineer with 14+ years of experience managing production infrastructure. Every design decision — from the dark theme to the copy-to-clipboard buttons on DNS values to the monospace font for record data — was made with practicing sysadmins in mind. No marketing fluff, just the tools you actually need when debugging DNS issues at 2am.