Tools
Every tool runs free, without an account.
DNS Tools
Email & Domain Authentication
Email Authentication Checker
Check a domain's SPF, DKIM, and DMARC records.
IP Address Tools
IP Geolocation Lookup
Look up the approximate location and ISP behind any public IP address.
Network Calculators
IP Address Converter
Convert an IPv4 address between dotted-decimal, binary, hex, and integer form.
Subnet Calculator (CIDR)
Convert between CIDR notation and subnet masks, and see usable host ranges.
Network Diagnostics
Port Checker
Check whether a port on a public host is open — handy for verifying port forwarding.
What Is My Proxy
See whether your connection is going through a forwarding proxy.
SEO Tools
Meta Tag & SEO Snapshot
Pull the title, meta description, canonical URL, and Open Graph tags from any page.
SSL & Security
HTTP Security Headers Checker
Check whether a site sends HSTS, CSP, and other browser security headers.
Webmaster Tools
Robots.txt & Sitemap Viewer
Fetch and read any site's robots.txt and listed sitemaps.
What Is My User Agent
Read your browser's user agent string, parsed into plain English.
Website Speed & Performance
Response Time & Header Checker
Measure server response time and inspect key response headers.
WHOIS & Domain Tools
WiFi & Router Tools
WiFi Network QR Code Generator
Turn your WiFi name and password into a scannable QR code.