SPF/DKIM/DMARC, mail header and bounce code analysis.
The tools in the Email category help you diagnose and fix the reasons your messages land in spam or bounce outright. In one place you can look up and generate SPF, DKIM, and DMARC authentication records, analyze raw message headers, decode 4xx/5xx SMTP bounce codes, set up BIMI brand logos, and run an all-in-one deliverability check on a domain. They're built for marketers sending newsletters and transactional mail, developers and ops engineers running a mail server or SaaS sending, and domain admins searching for things like 'why is my email going to spam' or 'how to set up SPF and DMARC.'
A typical workflow starts by checking the domain's current state. Look up its SPF, DKIM, and DMARC records for missing entries or syntax errors, then confirm the sending IP isn't listed on a DNSBL blacklist. If a message bounced or got filtered, paste the received message's raw header into the header analyzer to see which authentication step failed (softfail, permerror, and so on) and trace the relay hops and delays, then run the bounce code through the decoder to learn the cause and the fix. Every check is based on public DNS and standard mail specs, so after editing a record you simply re-run the lookup to confirm the result now passes, repeating until everything is clean.