COMPUTER CENTER / UTILITIES
Compare website reachability over IPv4 and IPv6
Inspect A and AAAA records and compare HTTP connectivity over IPv4 and IPv6. Distinguish target failures from unavailable IPv6 on the checking server.
IPv4 / IPv6
Inspect A and AAAA records and compare HTTP connectivity over IPv4 and IPv6. Distinguish target failures from unavailable IPv6 on the checking server.
How to use this tool
Enter a website URL. The tool reads both address families, selects an eligible public address in each family and attempts the same request. Compare the status and connection results to investigate cases where one family behaves differently.
Reading the results
Only a sample address from each family is tested, not every address behind a load balancer. If our server cannot make an IPv6 connection, the result explicitly reports that limitation. It does not label the target’s IPv6 service as broken merely because the checking location lacks IPv6 connectivity.
Tools index
23 utilitiesDNS changes
Compare a saved DNS snapshot with a fresh lookup.
DNS lookup
A, AAAA, MX, TXT and other DNS records.
DNS comparison
Compare answers from two public resolvers.
WHOIS / RDAP
Domain and IP registration records.
Reverse DNS / PTR
Reverse DNS and forward-confirmed hostnames.
Sites on this IP
Find indexed domains sharing an IPv4 address.
Mail journey
Read the route and reported authentication of an email.
SPF map
Explore SPF include and redirect dependencies.
Email DNS
MX, SPF and DMARC configuration.
SMTP check
Mail server banner, EHLO and TLS negotiation.
DKIM lookup
Public signing keys for a named selector.
Mail transport policies
MTA-STS policy and TLS reporting records.
Migration rehearsal
Check a new server before switching DNS.
IPv4 / IPv6
Compare a website over both address families.
Security contact
Find and review a site’s security.txt contact file.
Redirect trace
Follow the HTTP redirects of a web address.
Security headers
Review browser security policies in the response.
ASN & routes
Find the route prefix and autonomous system for an IP.
HTTP & TLS
HTTP headers and TLS certificate details.
TCP ping
Connection times on port 80 or 443.
Subnet calculator
Address ranges and subnet masks for IPv4 and IPv6.
My IP & connection
Your IP, network and proxy indicators.
DNS answers come from public resolvers. Registration data comes from the relevant registry. Results reflect the time and location of each check.
Visits and checks are recorded for site administration and abuse prevention.