Mailproof

Email deliverability test

Does your email really reach the inbox?

Send one message to a list of real mailboxes at the major providers. Within five minutes you will see, for every mailbox, whether it arrived, where it was filed and how it was authenticated.

Start the test

What the test checks

  • Delivery to real accounts at Gmail, Outlook, Yahoo, iCloud, GMX, ukr.net and more
  • Placement: Inbox, Spam, Promotions, Social, Updates or another folder, as classified by the provider itself
  • SPF, DKIM and DMARC verdicts taken from the receiving server's Authentication-Results header
  • Delivery time per mailbox and a delivery rate per provider and overall
  • A shareable result link and a PDF report for your team or client
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  1. Get the list of recipients

    Solve the small captcha to receive the current list of seed mailboxes. Copy all of them into the To (or Bcc) field of your email.

    Captcha image New image

  2. Add the identifier to your message

    Paste this unique code anywhere in the subject or body. It is how we recognise your message among everything else in the mailboxes.

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    Keep the rest of the message exactly as you would send it to customers: the same sender, template, links and images.

  3. Send the email

    Send the message from the system you want to test: your mail client, newsletter tool, CRM or transactional API.

    Tip: send to all recipients in one go so that every provider receives the same message at the same time.

  4. Check the result

    After sending, press the button. We will poll every mailbox for up to five minutes and show the status live. A mailbox that has not received the message by then counts as not delivered.

How it works

Four steps, one email

You copy our list of seed addresses, add a unique identifier to your message and send it from your usual mail system. We then watch each mailbox for five minutes and report what the provider did with your message.

Why test

Spam folders are silent

A message that lands in spam produces no bounce and no error. The only way to know is to look inside real mailboxes. Regular tests catch broken DNS records, blacklisted IPs and content problems before your customers do.

Privacy

Only your test message

We read headers of messages that carry your identifier and nothing else. Results are stored under an unguessable link and are never listed publicly.

Questions and answers

What is an email deliverability test?

It is a practical check of whether a message you send actually arrives in real mailboxes at different providers, and where it is filed: inbox, promotions, spam. Unlike a bounce, a spam placement is invisible to the sender, so the only reliable way to know is to look inside seed mailboxes.

Which mailbox providers are included?

The list is maintained by our team and typically includes Gmail, Outlook.com, Yahoo Mail, iCloud, GMX, ukr.net and other popular services. The current list of addresses is shown in step one of the test.

How long does a test take?

Results appear live as messages arrive. The check runs for five minutes; most providers deliver within seconds, so you usually have the full picture within a minute.

How are messages classified as Inbox, Promotions or Spam?

We do not guess. We read the folder or label that the receiving provider itself assigned: Gmail categories such as Promotions, Social and Updates, and the Junk or Spam folders of other providers.

What do the SPF, DKIM and DMARC results mean?

They are the authentication verdicts recorded by the receiving server in the Authentication-Results header. A pass on all three tells providers that the message genuinely comes from your domain, which is a prerequisite for good inbox placement.

Is the test free and is my message private?

The test is free. We only read the headers of messages carrying your identifier, and results are reachable only through an unguessable link that you can share with your team.

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