!rant

I learned something new while trouble shooting an email template today.

There was a weird margin at the end of my template and I have no idea where it came from. I inspected elements and found a 1x1 image.

Turns out it's a tracking link being loaded as an image.

Now I get why they call it a tracking pixel. It's literally 1 pixel.

I use thunderbird and never unset the "don't load images"-option, isn't this the norm? Why use tracking pixels in an email while every fucking link points to a tracking-service?

@YouAreAPIRate it's definetly not the norm. I'm working for a newsletter provider - most people get tracked by that.

I think that pixel tracks whether you open the email or not. It gotta be an image, so you don't need to click on it

@omnisyle yes You need to open and show images for it to load.

So it can then track when you open the email.

And unless you use gmail it can find you ip and unless you use some anonymization service i can roughly locate where you are ( city/ country).

Gmail loads all images through a proxy hiding all except that you opened it.

It also gets browservstring that usually tells which os and email client you use.

And some advanced once even can tell how long you where reading the email and if you forwarded it (at least edited it for forwarding)

Some email providers send out unique pixel links, so they can track every single recipient to see if they opened the mail or not. The links, too, are usually unique and routed via the mail provider's server so they can track if, when, which link you opened and how often. As from a perspective ofe someone who has worked on the newsletter sender's side: there is some impressive data available there. If you hook up a bit of machine learning: those newsletters are gonna write themselves in the future.

I'll be honest, I've used tracking pixels before surreptitiously.

It's useful because it can show data on where the user was when opening the email.

@Voxera that's very interesting. How do they track the time spent on the mail? Are they making a keep alive request and check when it gets canceled?

@plusgut sort of.

They do not return the response directly but wait for say 30 seconds then return a redirect to the same url with a new counter number to avoid cache.

And when the client browser/email client either sends a disconnect or stop requesting the new pages they assume that you closed the email.

Not 100% accurate but enough.

@Voxera oh wow, that really is interesting, thank you.