Almost every email you receive from companies contains a tracking bug. The sender receives an alert when you open the message to read it. Knowing this, it is possible to block this feature or use it yourself to track your messages.
How are emails tracked?
In theory, email is a very simple communication medium. But in reality, you're not just sending someone a text message – emails can contain HTML code, like on web pages. They can also load images, that's how tracking works.
When you open an email, your email client loads the images in the email from the remote server and displays them, much like when you open a web page. You can tell your email client to never load images if you want, but it usually loads them by default.
Companies that send email newsletters or other automated emails almost always include a specific tracking image. This is a tiny, invisible image file that is only one pixel long, also known as a pixel tag or web beacon. Each newsletter recipient is assigned a unique tracking code within this image. These images are also known as “web beacons.”
When you open the newsletter, and it loads images (even if you can't see them), it also loads a web beacon. When this specific image is loaded from the company's servers or a third-party service, the sender can then know that the email sent to your address has just been opened.
There are other ways to track the messages you receive. For example, each link in the email can have a unique identifier, unique to you, so we can see which links you clicked on. But tracking only happens when you click on a link, not when you open the email.
Why do people track email opens?
There is generally nothing dangerous or unhealthy about this type of tracking. It is a widespread practice. Companies that send newsletters need to know how many people open and read them in order to improve their targeting or the content of their mailings.
Everyone does it. At Byothe.fr, we use this type of tracking for our newsletter. This allows us to ensure that we only send it to people who are interested in it. If a person never opens or interacts with our newsletter, we can remove them from the mailing list and stop bothering them with our emails.
By the way, individuals can also use tracking tools. For example, if you are looking for a job and you send CVs left and right… it can be quite interesting to know who opened your email! There are software programs that integrate tracking images to allow you to know who reads your emails.
Email open tracking doesn't always work
It’s not a perfect system. In fact, it’s pretty messy. There are many reasons why an email open tracking system might not work properly.
If the recipient is using an email client that is configured to not load images, the tracker will not load and you will have no way of knowing if that person has viewed the message. This is also true if the recipient is using software that blocks these tracking images.
Some software, in which the message will pass on its way to your mailbox, may load the tracking image for some reason, such as to provide a preview of the email or to scan everything in it for viruses. You may get a message that the email has been viewed even if the recipient never opened it.
More drastically, some professional email systems can even block all incoming emails containing tracking images or links.
But regardless and despite its imperfections, it is the only solution that exists in the industry to track messages, so people still use it.
How to block email opening tracking?
If you don't want people to know that you opened the message they sent you, you can easily fix this by changing a setting in your email client: disable automatic loading of images.
For example, in Gmail go to Settings > General > Images and select the option " do not automatically load images » without forgetting to save by pressing « Save Changes » at the very bottom of the page.
So, when you open an email containing images, you will now see two new options at the top of it:
- « Show images below » to display images punctually in the email in question
- « Always display images from xxx@mail.fr » to allow images from the sender in question if you trust them.
People can only see if you opened the email if you choose to show images.
The system is more or less the same on most email systems. You will always find an option to prevent it from automatically loading images from messages.
Article updated on January 5, 2025 by Byothe
