Free Developer Tools

Check the age of any domain name instantly. Get registration date, expiration date, and domain age in years, months, and days with our free Domain Age Checker tool.

Test if a website supports IPv6. One live DNS lookup checks a domain's AAAA records, name servers, and mail servers, and scores each layer so you can see where IPv6 coverage stops.

Look up any AS number for the organization behind it, every IPv4 and IPv6 prefix it announces, its BGP upstreams, downstreams and peers, and the registry WHOIS record.

Find out why a certificate is being rejected: expired, covering the wrong name, or missing the intermediates that browsers and API clients need. Works on any domain.

Check whether any IP address is a VPN, proxy, residential proxy, Tor exit node, or datacenter — or check your own connection in one click. Names the provider or hosting company where known.

Parse any user agent string instantly to identify browser name, version, device type, OS, and rendering engine. Get structured results in JSON format.

Use Our tool to Check if your domain has DNSSEC (DNS Security Extensions) enabled. Ensure your domain is protected against DNS spoofing and cache poisoning attacks by validating the presence of DNSSEC signatures.

Find IPv4 & IPv6 addresses up to 100 domain names at once with our free bulk domain to IP lookup tool.

Verify whether a website sends the Strict-Transport-Security header and confirm if HSTS is enabled. Inspect HSTS policy settings to ensure secure HTTPS-only connections.

Find every domain hosted on an IP address with a reverse IP lookup tool that discovers domains pointing to any IPv4 or IPv6 via DNS A records, complete with an exact domain count for security research, server audits, and infrastructure investigations.

Enter any name server to see which domains delegate their DNS to it. Run a reverse NS lookup with exact or wildcard matching, plus TTL and last-seen dates.