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Pre-check by email
Send one message to a temporary address and see whether it passes SPF, DKIM and DMARC. A first step when your emails are going to spam or bouncing.
- 1Create an address
- 2Send an email
- 3Read the results
Create a temporary address to send to
Only the first message each address receives is analyzed. Send one under 2 MB, without attachments.
Only this browser can open the results. The address and the results expire after one hour, and the message body isn't kept in the results.
What one message tells you
This analyzes a message that really arrived, not your DNS settings.
SPF
Whether the sending server's IP is in the SPF record of the bounce address (Envelope From) domain.
DKIM
The signatures on the message are verified, and you see which domain and selector signed it.
DMARC
Whether a domain that passed SPF or DKIM matches the domain in the From address. If none does, DMARC fails even when both pass.
Authentication headers
The authentication headers the receiving server added, such as Authentication-Results, shown as they are. The body and attachments aren't displayed.
Frequently asked questions
What should I send?
Send the way you normally would from the service you want to check: work email from your email client, newsletters or notifications with that service's test-send feature. Results differ by service, so check each one separately.
Gmail bounces my mail with 550 5.7.26. Can this find the cause?
550 5.7.26 means the message did not pass SPF or DKIM authentication, or was refused under your domain's DMARC policy. Send a message to this address the same way the bounced one was sent, and you will see which check fails and why.
What happens to the message I send?
Only the first message each address receives is analyzed. The results can be opened only in the browser that created the address, and the address and results expire after one hour. The message body isn't kept in the results, and the raw message is normally deleted within 2 days of being analyzed.
After the pre-check, read your DMARC reports
A pre-check shows only what your domain publishes today and what one message did. With DMARC reports you see who is sending email as your domain, and the tasks that take you to p=reject, in order.