CNAME Lookup

Look up the CNAME (canonical name) record on any DNS name. CNAMEs alias one name to another — common in custom-domain wiring (e.g. www.example.com → example.web.app), ESP DKIM CNAME chains (e.g. selector._domainkey.example.com), and CDN setups.

When to use this

Custom-domain hosting: verify your www CNAME points at the right hosting provider.
DKIM via CNAME: ESPs like Mailchimp, Postmark, and SendGrid issue DKIM as CNAME records you publish at selector._domainkey.yourdomain.
Custom email subdomain: Resend / SES setup often involves CNAMEs at send.r1.yourdomain or similar.
SaaS sub-domain: tools like Notion, Webflow, and Vercel hand you a CNAME target to point your custom domain at.