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dalerus

Did you track open rates? I would be curious to see what those numbers look like.

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I thought about this, but I couldn't think of a way to do it reliably without setting of more spam alarms.

Is there any reliable way to do this? Most mail clients will block receipt-type stuff by default...

I believe the trick is to put a hidden, 1px image in the email. Then you can track how many times it was requested.

Assuming people read their email in HTML and has their email client set/defaulting to automatically requesting external content. Sure, for a large sample from non-technical audience such as here it's probably a good assumption, but it may not be for e.g. a small sample from a tech-savvy audience.

Most modern email clients (and webmail clients, and smartphone clients) hide webbugs by default, so the 1px image technique won't work.

This'll only work on very very old desktop clients, or users that actually click the "show images" button.

How many mail clients load those by default nowadays? Gmail doesn't, Thunderbird doesn't.

Um, Gmail does: https://support.google.com/mail/answer/145919?hl=en

> Gmail automatically shows you the images in your messages

It does have an option to turn it off, but the default is on. They will load up the image themselves, then serve it from their domain, but, as the help information shows, that still indicates an "open", it's just that all the information on who opened the email (IP address, etc) would be wrong.

I believe gmail is caching these images on their own servers.

One source: http://arstechnica.com/information-technology/2013/12/gmail-...

EDIT: I get what you're saying. I guess the count would depend on how long Google caches that image- or do they load it on a per email basis?

Yep, we're on the same page. The wording they use is "In some cases, senders may be able to know whether an individual has opened a message with unique image links." but I'd expect the tracking URLs themselves to be unique (most are, they are tied to an email so they know who opened the email and who didn't) so they would most likely bypass this cache. I expect the "some cases" refers to the ones where it simply gives you a count of people who opened your email, and does it by simply having a generic tracking URL.

D'oh, thanks for the correction! I knew about their caching mechanism, but failed to realize that it wouldn't prevent this sort of tracking pixel from working due to the pixel URL being unique (in most cases).

Most reputable email clients won't load remote images in email messages.

I'm familiar with the tracking image "trick" but I assumed most email clients wouldn't load those by default. The other comments seem to indicate I was wrong. :(

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