Domain, email & website tools
Free tools for domains, email and the web. Look up a record, investigate a connection or check a certificate—with explanations that help you understand the result.
Domains & DNS
DNS Record Lookup
Find the records that connect a domain to websites, email and other services.
Nameserver Lookup
Find the nameservers published for a domain to help identify where its DNS is managed.
Reverse DNS Lookup
Look up the hostname associated with a public IPv4 or IPv6 address.
CAA Record Lookup
See certificate-authority authorisation records published at a domain name.
IP Address Lookup
Enter a public IP address to find its network, ASN and approximate location.
WHOIS Lookup
Look up domain registration dates, registrar and publicly available registration information.
What Is My IP?
Check your own public IPv4 and IPv6 addresses, provider and approximate location.
MX Lookup
See which mail servers receive email for a domain and the order in which senders try them.
SPF Record Checker
Read your domain’s SPF policy and spot common record configuration problems.
DKIM Record Checker
Find a domain’s email-signing public key using its DKIM selector.
DMARC Record Checker
Read the email authentication policy published for a domain and understand its instructions.
Websites
New to DNS and email records?
Start with our beginner’s guide to DNS records. Each lookup page also explains what its results mean—and what they cannot tell you.
Need help applying what you find? We can help with your website or business email.