Email Deliverability Tester
Instantly test SPF, DKIM and DMARC using a unique email address.
Generate a unique test address, send an email, then view a permanent results page.
Your unique test email address
72997682b8765307a9d04ebe0ba5a991fdee@mail-tester.co.uk
Send an email to the address above. Once received, refresh the results page.
What we check
SPF
Pass/fail (rspamd or headers)
DKIM
Signature result (if present)
DMARC
Alignment + policy result
Content
Size, links, images, attachments, text/HTML balance
Note - Authentication can pass even if the content is low quality. Content score handles that separately.
Closed the window by mistake?
Paste the test email address you copied earlier (or just the token part) and we will take you straight to your results.
Retrieve results
Tip - You can paste the full email (token@mail-tester.co.uk) or just the token.
Email Deliverability FAQs
How does Mail-Tester.co.uk work?
We generate a unique test address. Email it, then view a permanent results page with authentication and content signals.
What do you check?
We check SPF, DKIM and DMARC signals, key headers and sender IP, plus content factors like links, size, images and attachments.
Why can SPF, DKIM and DMARC pass but emails still hit spam?
Authentication proves identity, but inbox placement also depends on sending reputation, content quality, sending patterns and recipient engagement.
Need help improving deliverability? Run a test, then use the help form on the results page.