Email Deliverability Checker

How the Email Deliverability Checker Works

This tool queries your domain's DNS records to audit email authentication:

1. MX records, verifies your domain has mail exchange records pointing to email servers. Also detects your email provider (Google Workspace, Microsoft 365, Zoho, etc.).
2. SPF validation, checks for an SPF TXT record, validates the syntax, detects dangerous mechanisms like +all, and counts DNS lookups (10-lookup limit).
3. DKIM detection, scans 17 common DKIM selectors (google, default, selector1, brevo, mandrill, etc.) to verify DKIM signing is configured.
4. DMARC analysis, checks for a DMARC record, evaluates the policy (none/quarantine/reject), verifies report addresses (rua/ruf), and flags percentage restrictions.

Why Email Authentication Matters

Email authentication is no longer optional, it's required by major inbox providers:

• Google and Yahoo requirements (2024), bulk senders must have SPF, DKIM, and DMARC configured or face delivery failures. Even small senders see improved delivery with proper authentication.
• Spoofing and phishing protection, without SPF, DKIM, and DMARC, anyone can forge emails that appear to come from your domain. Phishing attacks using your domain damage brand reputation and customer trust.
• Inbox placement vs spam folder, properly authenticated emails are significantly more likely to reach the inbox. Missing authentication is one of the top reasons legitimate emails get filtered to spam.
• Domain reputation, email providers track domain reputation over time. Consistent authentication builds a positive sending reputation that improves deliverability for all your emails.
• Business email reliability, when clients, customers, or leads don't receive your emails, you lose revenue. Proper authentication ensures your transactional emails, newsletters, and business communications arrive reliably.

After checking email authentication, verify your domain's DNS setup with our DNS Lookup tool and check your SSL certificate with the SSL Certificate Checker. Also run a security headers check to ensure your web server is hardened alongside your email setup. For full domain intelligence, the WHOIS Lookup shows domain registration, registrar, and expiry details.

How to Fix Email Authentication Issues

Common fixes for email deliverability problems:

• Missing SPF, add a TXT record to your DNS with v=spf1 include:_spf.google.com ~all (replace with your provider's include). Use ~all (soft fail) or -all (hard fail).
• Missing DKIM, enable DKIM signing in your email provider's settings. Google Workspace, Microsoft 365, and most providers offer one-click DKIM setup that adds the DNS record automatically.
• Missing DMARC, add a TXT record at _dmarc.yourdomain.com with v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com. Start with p=none to monitor, then upgrade to p=quarantine or p=reject.
• SPF +all, change +all to ~all or -all immediately. +all means anyone can send as your domain, defeating the purpose of SPF entirely.
• Multiple SPF records, merge into a single record. Having more than one SPF record causes authentication failures per RFC 7208.
• DMARC p=none, after monitoring reports for 2-4 weeks, upgrade to p=quarantine (spam folder) and eventually p=reject (block). p=none provides no protection, it only monitors.

For help setting up email authentication and improving deliverability, explore our SEO services which include technical site audits covering email DNS configuration.