How does a newsletter know you opened the email?
An invisible image and personalised links tell the sender when you open, where you are and what you click. How it works and how to block it in a minute.
You open a newsletter, have a quick look, close it. For you, that’s the end of it. For the sender, a piece of information has just arrived: you, specifically you, opened it at 7:42, on your phone, from your home network.
How does the sender know I opened the email?
With an image you can’t see. The message contains a tiny image, often a single transparent pixel, that isn’t inside the email but on one of the sender’s servers. Its address contains a code that identifies you.
When your email program displays the message, it downloads the image. The sender’s server receives the request and records:
- that you opened the message, and how many times;
- when, to the second;
- where from: the network address reveals your internet provider and often your town, or the company you’re connecting from;
- with what: your email program and the type of device.
What about the links?
Links talk too. In newsletters, links don’t usually take you straight to the website: they first go through an address belonging to the sender that contains the same personal code, then send you on to the page. So the sender knows which link you clicked, and when.
That’s why, after clicking on an offer, you sometimes get a second message about exactly that offer.
Has anyone already solved the problem?
Partly. Two well-known examples:
- Since 2013, Gmail has downloaded images through its own servers: the sender can’t see your network address, but still knows you opened the message.
- Since 2021, with iOS 15, Apple Mail has offered “Mail Privacy Protection”, which downloads remote content anonymously in advance: the open signal becomes unreliable.
These are useful solutions, but they depend on the program you use and on a service run by whoever provides it.
How do I block newsletter tracking?
Block remote images until you ask for them. Almost every email program has this option, often tucked away in the privacy or security settings. From then on:
- messages open with their text and without external images;
- the pixel isn’t downloaded, so the open isn’t recorded;
- for senders you trust, press “Show images” or add them to your trusted list.
For links, check where they lead before you click: if you hold your finger or the mouse over a link, many programs show the real address.
What do the Akomodix apps do?
They start out blocked. In the Akomodix apps, for web, iPhone, Android and desktop, remote images don’t load until you decide, and before you open a link you see the real site, not the text the sender chose to show you.
In the meantime, you can take the step that matters right now, in the program you use: look for the setting that loads remote images automatically and turn it off. It takes a minute, and from the next newsletter onwards, you decide what the sender knows about you.
Frequently asked questions on this topic
Can the tracking pixel see the content of my emails too?
No. The pixel only records that its image was downloaded: when, how many times, from which network address and with which program. It doesn't read the rest of your mailbox. The problem isn't the content, it's the profile being built: what time you read, from where, how often, and whether you opened that particular offer.
If I block images, will I stop seeing newsletters?
You'll still see them, just without images until you press "Show images". For senders you trust, you can always show them. The text stays readable and the links work. It's the same trade-off many professional email programs make: ask first, then load.
Do reputable companies use tracking pixels too?
Yes, almost every newsletter platform adds one by default to measure how many people open a message. On its own, it isn't a sign of bad faith. But it's a measurement taken without asking you anything, and that's why it's right for your email program to let you decide.