What is email tracking?

Email tracking is what happens after you click send. It records whether your message was opened, at what time, how many times, on what kind of device, from roughly where, and whether the links inside it were followed. Ordinary email gives you none of this. You write, you send, and the message disappears into someone else's inbox where you have no visibility at all until they choose to reply. Tracking closes that gap, partially and imperfectly, and this page explains exactly how — including the parts that do not work.

The tracking pixel: how an open is recorded

The mechanism is older than most people expect and simpler than they imagine. When you send a tracked message, a tiny image is embedded in the body — historically a transparent one-pixel GIF, which is where the name comes from. That image is not attached to the email. It sits on a server, and the message contains only an address pointing at it, with a unique identifier attached to that address.

Email is fundamentally a web technology in this respect. When your recipient's mail client displays a message containing remote images, it makes an HTTP request for each one, exactly as a browser does when loading a page. Our server receives that request, sees the identifier, and knows which message was just displayed. From the request itself we learn the time, the IP address it came from, and the user-agent string, which identifies the mail client and operating system.

Everything else follows from those three facts. The IP address gives an approximate location through IP geolocation. The user-agent tells us whether it was opened on an iPhone, an Android phone, a desktop version of Outlook, or a browser. The timestamp gives you the moment, and repeated requests give you a sequence of opens rather than a single event.

You will see the term "web beacon" used for this. It is not a separate technique — a web beacon and a tracking pixel are the same thing under two names, one of them borrowed from advertising terminology. There is no second, more sophisticated mechanism hiding behind the jargon.

Link tracking: the other half, and the more reliable half

The genuinely different technique is link tracking. Instead of putting your destination URL directly in the message, the tracker replaces it with its own address carrying an identifier. When the recipient clicks, the request reaches the tracking server first, which records the click and immediately redirects the reader onward to where they were going. The redirect is fast enough that nobody notices it.

Link tracking is worth understanding separately because its data is stronger than open data in two ways. Opening an email costs nothing and can happen by accident, in a preview pane, or automatically. Clicking a link is a deliberate act by a person who decided your message was worth acting on. And a click comes directly from the recipient's own connection, which means it survives the proxy problem described below — when an open gives you no usable location, a click often still does.

What tracking cannot see

This is the part most explanations skip, and it matters more than the mechanism.

Tracking never sees inside the message. The pixel request carries an identifier, an IP address and a client string. It carries no content. We do not know what you wrote, and neither does any other tracker built this way.

An open is not a read. A message displayed in a preview pane for two seconds while someone scrolls past registers identically to one read carefully twice. Opens measure attention reaching your message, not comprehension or interest. Clicks are the better proxy for interest.

Blocked images mean no record. If a mail client or a corporate gateway refuses to load remote images, the pixel never loads and no open is recorded — even though the message may have been read closely. This is the crucial asymmetry: an open you receive is solid evidence that something happened, while the absence of an open is weak evidence that nothing did.

Nothing identifies a person. Tracking tells you a connection in approximately a certain place displayed your message. It cannot tell you who was holding the device, and IP geolocation resolves to a city rather than an address.

Proxies, and why some trackers report opens that never happened

Two changes over the past decade reshaped how this technology behaves, and any current explanation that ignores them is out of date.

Google began routing images in Gmail through its own servers in 2013. When your recipient uses Gmail, Google fetches and caches the pixel rather than letting their device request it directly. The open is real, but the IP address reaching us belongs to a Google data centre, so the location it resolves to is a building full of servers rather than a person. This is worth being precise about, because it is widely misreported: Gmail does not block tracking. It displays remote images by default and has done for years. What it does is anonymise the location.

Apple Mail Privacy Protection, introduced with iOS 15 in 2021, goes further. It routes image requests through Apple's relay and, more consequentially, pre-fetches images for messages regardless of whether the recipient ever opens them. For a tracker that logs every request naively, this manufactures opens that never occurred — and since MPP covers a large share of consumer mail, the resulting statistics are not slightly inflated but structurally unreliable.

Handling this correctly is the main technical difference between email trackers today. GeoTrack identifies requests originating from proxy infrastructure and data-centre ranges rather than from consumer connections, filters the automated pre-fetches out of your timeline, and marks genuine proxied opens as confirmed without attaching a fictional location to them. A tracker that shows you a confident map pin for every Gmail recipient is showing you where Google's servers are.

Is email tracking legal?

Generally yes, with conditions that have tightened considerably, and the answer depends on where your recipients are rather than where you are.

In the European Union, an IP address counts as personal data following the Court of Justice ruling in Breyer (C-582/14, 2016), so tracking opens is processing personal data under the GDPR and requires a legal basis, a defined purpose and a retention limit. France went further and specified the position for email in particular: the CNIL published its recommendation on tracking pixels on 14 April 2026, treating them as trackers under Article 82 of the Loi Informatique et Libertés and requiring prior consent for most marketing uses. A transitional window allowed organisations three months to inform existing contacts and offer an opt-out; it closed on 14 July 2026, and the CNIL has said it will be checking compliance from that point. The obligation applies to B2B correspondence as well as consumer marketing, and it is the purpose of the pixel that determines the requirement rather than the type of message carrying it.

In the United States there is no equivalent federal rule for tracking pixels, though CAN-SPAM governs commercial messages generally and several state privacy laws now apply to the underlying data. Elsewhere the picture varies, and the practical rule for anyone sending internationally is to comply with the strictest regime their recipients fall under.

We built the opt-out mechanism into the product rather than leaving it to you, and we process data under a formal Data Processing Agreement. Our privacy policy states what we retain and for how long — never the contents of your emails.

How GeoTrack does it

We have kept email tracking to its simplest useful form. Install the extension, write in Gmail exactly as you always have, and send. Tracking is applied automatically, and your opens, locations, devices and clicks appear in a sidebar beside your sent messages, with a notification the moment something happens. There is no separate application and nothing to export.

Tracking is free for life for basic use, with paid plans for unlimited tracking and the full geolocation and analytics features. Subscriptions fund the product entirely — no ads, no data sales, no outside investors.

Common questions

Can my recipient tell they are being tracked? Not from reading the message normally. Someone examining the raw HTML would find the image and the rewritten links. Whether you should disclose it is a separate question from whether it is detectable, and in the EU disclosure is increasingly an obligation rather than a choice.

Can I track a reply? No. Tracking applies to messages you send. What arrives back is an ordinary email.

Does tracking hurt deliverability? A remote image and rewritten links are standard practice across every email platform in existence and are not themselves a spam signal. Volume, list quality and sending reputation are what determine placement.

Why do I see several opens for one message? Because the recipient displayed it more than once, or reopened it on another device, or forwarded it to someone who opened it in turn. Repeat opens from different cities are one of the more useful signals you can get — see the benefits of email tracking.

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The benefits of email tracking
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