Check your domain's email authentication in seconds. Validate DNS records, test deliverability, and find misconfigurations before they cause problems.
Enter a domain, get instant results
Verify record syntax, policy strength, alignment settings, and reporting configuration.
Validate SPF records, count DNS lookups against the 10-lookup limit, and detect providers.
Verify DKIM keys across common selectors, check key strength, and detect weak keys.
Validate MTA-STS DNS records, HTTPS policy files, mode configuration, and MX alignment.
Check BIMI records, logo availability and format, and VMC certificate authority.
Validate TLS-RPT DNS records, reporting destinations, and STARTTLS support.
Beyond DNS lookups
Send a real email to a test address and get a full deliverability report: SPF, DKIM, DMARC alignment, blocklist checks, content analysis, and a 0-100 spam score.
Build a valid SPF record by selecting your email providers. Generates a ready-to-paste DNS TXT record.
These tools give you a one-time check. MailShield monitors all your domains 24/7 with alerts, DMARC report processing, and security scoring. Free for up to 2 domains.