Free Domain & DNS Developer Tools
Check DNS records, SSL certificates, WHOIS data, and more. Built for developers working with domains and custom domain setups.
SSL
Free SSL Certificate Checker
View issuer, validity, expiration countdown, and certificate chain for any domain.
Open tool →DNS
Free DNS Record Lookup
Check A, AAAA, CNAME, MX, TXT, NS, and SOA records for any domain instantly.
Open tool →Domain
Free WHOIS Lookup
View registrar, creation and expiry dates, name servers, and registration data for any domain.
Open tool →DNS
Free CNAME Lookup & Generator
Validate CNAME records and get provider-specific setup instructions for custom domains.
Open tool →HTTP
Free HTTP Header Checker
Inspect response headers, security headers, caching, redirects, and get a security grade for any URL.
Open tool →DNS
Free DNS Propagation Checker
Query DNS servers across multiple global locations to verify your DNS changes are live.
Open tool →Other
Free Custom Domain Cost Calculator
Compare building in-house vs. using a managed service for custom domains on your SaaS.
Open tool →HTTP
Free Redirect Checker
Trace the full redirect chain for any URL. See each hop with status codes, response times, and the final destination.
Open tool →Free SPF Record Checker
Look up and validate SPF records for any domain. Check for syntax errors, DNS lookup limits, and common issues.
Open tool →Domain
Free Domain Age Checker
Check how old any domain is. See exact registration date, age, last updated, and expiration.
Open tool →Domain
Free Subdomain Finder
Discover subdomains for any domain using DNS enumeration and certificate transparency logs.
Open tool →DNS
Free Reverse IP Lookup
Find the hostname associated with any IP address. PTR (reverse DNS) lookups in one click.
Open tool →Free DMARC Record Checker
Look up and validate DMARC records. Check policy settings, alignment, and reporting configuration.
Open tool →DNS
Free TXT Record Lookup
Look up and categorize TXT records. Identify SPF, DKIM, DMARC, verification tokens, and more.
Open tool →HTTP
Free Website Status Checker
Check if any website is up or down. See response time, HTTP status, and SSL certificate status instantly.
Open tool →Free DKIM Record Checker
Look up and validate DKIM records for any domain and selector. Verify key configuration and common issues.
Open tool →Domain
Free Domain Availability Checker
Check if a domain name is available across multiple TLDs (.com, .io, .dev, .app, .co, and more).
Open tool →Building a SaaS that needs custom domains?
These free tools are built by the team behind Domainee — the API for adding customer custom domains to your product. One CNAME, automatic TLS, no DevOps to staff.
50 custom domains and 100 GB bandwidth free, forever.