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Postmark Spam Score API in the Wild - and Christmas is Saved on Reddit

A few weeks ago we released a free API for checking the spamscore of a message. The folks on HackerNews loved it, and it’s been really great to see people find ways to get more value from this API.

Some of our favorite usages have shown up in just the last week!

We released our Spam Checking API with an easy and beautiful UI, but it does require that you grab the full email contents including the headers. Simple as this is, it’s work. Wouldn’t it be great if you could just forward an email somewhere, and moments later, get back a nicely formatted report about your email’s spamscore?

An email response sent from

That’s exactly what Jim Carter built with The cool thing about is there’s no interface other than your email client! Just forward any email to and get one of these bad boys back.

It’s free (but no less awesome), so please be kind to Jim’s servers. Have other ideas for useful mashups with our spamscore API? Let us know in the comments, or better yet email me once you’ve launched so we can write about it here!

Christmas is saved on Reddit

Our hearts were warmed to find that someone recommended our spamscore checker to a Reddit user whose christmas eCards were being sent to spam.

Spamscore saved the day for one Reddit user

Chris was able to jump in and do a quick analysis of the person’s spamscore report, recommending the following to help with the resolution:

  • Set your Return-Path header to a domain and address that you control. Then, add an SPF record to that domain with the permitted SMTP servers.
  • Do not use your user’s email as the from address. This is spoofing and you can’t control the DKIM or SPF. Instead, use their “From name” but your email address.
  • Make sure Reverse DNS is setup for your SMTP server.

While we can’t promise personal spamscore report interpretation for every problem, we’re thrilled to see that this tool is being used to help solve real world problems in people’s applications.

Have you used the spamscore API to successfully track down a problem? Let us know in the comments.

Alex Hillman