WHOIS / RDAP
Domain registration lookup utilities used when verifying ownership and DNS stewardship.
Overview
Domain registration lookup utilities used when verifying ownership and DNS stewardship.
Vendor: ICANN / registrars
Primary purpose
Confirm domain registration and registrar contacts during investigations.
Best for
- Ownership and registrar checks during incidents
Common use cases
- Find registrar for DNS changes
- Confirm domain age context
Advantages
- Universal starting point for domain ownership questions
Limitations
- Privacy redaction hides contacts
- Not a mail diagnostic
When not to use it
- You need authentication record validation (use dig/MXToolbox)
Pricing
Free public lookups (rate limits vary).
Official website
Inputs and outputs
Typical inputs
- Domain name
Typical outputs
- Registration metadata
Privacy notes
- Review each vendor’s data handling before uploading production lists or message content.