Free Tools
What's My IP
Public IP, ISP, location & VPN status
Popular
SSL Checker
Certificate validity, expiry & chain
TLS Checker
Detect weak ciphers & TLS versions
WHOIS Lookup
Domain registration & expiry data
DNS Lookup
A, MX, TXT, NS, CNAME records
DNS Propagation Checker
Global DNS propagation status
Security Headers Checker
Check HTTP security header grades
HTTP Header Checker
Inspect raw HTTP response headers
Domain Expiry Checker
Days until a domain expires
DNSSEC Checker
DNS security validation
DMARC & SPF Checker
Email security & anti-spoofing setup
Uptime Checker
Live availability & response time
Secret Scanner
Find hardcoded keys & credentials
New
Dependency Checker
Known CVEs in your packages + SBOM
New
IaC Scanner
Terraform, Kubernetes & Docker config
New
JWT Decoder
Decode & inspect JSON Web Tokens
New
JSON Formatter
Format, validate & minify JSON
New
Base64 Encoder
Encode & decode Base64
New
Hash Generator
SHA-1/256/384/512 digests
New
Regex Tester
Test regex with live matches
New
CNAME Lookup
Trace hostname aliases
New
MX Lookup
Mail servers & priorities
New
CVSS Calculator
CVSS v3.1 score & vector
New
CORS Checker
Cross-origin policy & reflection
New
Redirect Checker
Trace the full redirect chain
New
Technology Detector
What a site is built with
New
Email Security Checker
Every email record, scored
New
Blacklist Checker
DNSBL & email blocklist lookup
New
Subdomain Finder
Find subdomains via CT logs
New
Certificate Transparency Checker
Search CT logs for a domain
New
Certificate Decoder
Decode a PEM certificate
New
Certificate Chain Checker
Find missing intermediates
New
CVE Lookup
CVE & GHSA vulnerability search
New
Dockerfile Security Checker
Container build misconfigurations
New
API Security Checker
What an anonymous caller sees
New
OpenAPI Security Analyzer
Audit an API specification
New
IP Address Lookup
ASN, network owner & rDNS
New
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