An email tracking pixel is a tiny, invisible image (usually 1×1 pixel) hidden in an email. When your email app loads it, the sender's server records that the message was opened, along with when, roughly where, and on what device. You can block most tracking pixels by turning off automatic loading of remote images in your email app.
Tracking pixels are everywhere. Newsletters, marketing campaigns, sales outreach tools and even some one-to-one emails use them. They aren't malware and they can't read your inbox, but they do report on your behaviour without asking.
What it is: an invisible image with a unique link tied to you.
How it works: opening the email loads the image, and that request tells the sender's server you opened it.
What it reveals: open time, number of opens, approximate location from your IP address, and device or email app.
How accurate it is: less than senders think. Image proxies and Apple Mail Privacy Protection blur or inflate open data.
How to block it: turn off automatic remote image loading, use your app's privacy features, and load images only for senders you trust.
What it can't do: see your other emails, your files, or whether you actually read the message.
How does an email tracking pixel work?
A tracking pixel works because most email apps load images from the internet automatically. Each pixel's web address is unique to you, so the sender knows exactly who triggered it.
The sender adds a hidden image. Their email platform inserts a transparent 1×1 image at the bottom of the HTML email. You never see it.
The image link is personalised. The address looks something like
https://track.example.com/open?id=8f3a2c, where the ID is tied to your email address and that specific campaign.You open the email. Your email app sees an image and requests it from the sender's server.
The server logs the request. It records the time, your IP address (which suggests your rough location), and your device and email app from the request details.
The sender's dashboard updates. The email is marked "opened." Each new open is usually logged again.
The same idea powers link tracking: links in the email are rewritten to pass through the sender's server before reaching the real page, which records every click.
Tracking pixels vs read receipts
Tracking pixel | Read receipt | |
|---|---|---|
Visible to you? | No | Yes, your app asks before sending one |
Your permission needed? | No | Yes |
Who uses it | Marketing tools, sales outreach, newsletters | Individual senders in business email apps |
How to stop it | Block remote images | Decline the receipt request |
What can senders learn from a tracking pixel?
A tracking pixel reveals more than "opened or not," but far less than many people fear.
What senders can see | What senders can't see |
|---|---|
That the email was opened, and how many times | Whether you actually read it |
Date and time of each open | Your other emails or contacts |
Approximate location, from your IP address | Your exact address |
Device type and email app | Files on your device |
Whether you clicked a tracked link | Your password or account details |
Whether the email was forwarded and opened elsewhere (sometimes) | Anything if images never load |
How accurate is open tracking?
Less accurate than most dashboards suggest. Two big changes blurred the data:
Image proxies. Gmail and several other providers fetch images through their own servers. The sender still sees an open, but usually not your real IP address or location.
Apple Mail Privacy Protection. When turned on, Apple Mail loads remote content privately in the background, whether or not you open the email. That hides your IP address and can make emails look "opened" when they weren't.
The result: open rates are now a rough signal, not proof. Senders who care about accuracy rely more on clicks and replies. If you send email yourself, our guide to email deliverability best practices explains which metrics still matter.
How to block email tracking pixels
The most effective way to block tracking pixels is to stop your email app from loading remote images automatically. You can still show images for senders you trust with one click.
Email app | Where to find it | Setting to choose |
|---|---|---|
Gmail (web) | Settings (gear icon) → See all settings → General → Images | "Ask before displaying external images," then Save Changes |
Gmail (Android and iOS) | Settings → your account → Images | "Ask before displaying external images" |
Outlook (classic Windows app) | File → Options → Trust Center → Trust Center Settings → Automatic Download | Keep "Don't download pictures automatically" ticked |
Outlook.com and new Outlook | Settings → Mail → Privacy and data | The option that stops external images loading automatically |
Apple Mail (iPhone and iPad) | Settings → Mail (Settings → Apps → Mail on newer iOS) → Privacy Protection | Turn on "Protect Mail Activity" |
Apple Mail (Mac) | Mail → Settings → Privacy | Turn on "Protect Mail Activity" |
Thunderbird | Settings → Privacy & Security | Leave "Allow remote content in messages" unticked (the default) |
Menu names change between app versions, so look for wording like "external images," "remote content" or "privacy."
Extra steps for stronger privacy
Be careful with links. Blocking images doesn't stop link tracking. If privacy matters, type the website address yourself instead of clicking.
Read in plain text where your app offers it. Plain text shows no images at all.
Unsubscribe from senders you don't trust. Fewer marketing emails means fewer pixels.
Use a privacy-focused provider. The right mailbox protects you by design instead of by settings you have to remember.
How to tell if an email is being tracked
You can't always be sure, but these signs point to tracking:
It's a marketing or sales email. Almost every newsletter platform and sales outreach tool tracks opens by default.
Your app shows a "load images" prompt on an email that looks mostly like text. A text email with a hidden image is a classic sign.
Links look long and strange when you hover over them, often passing through a different domain from the sender's.
The sender follows up suspiciously fast right after you open their message.
For the technically curious, viewing the original message source and searching for tiny images (width="1" height="1") or unfamiliar image domains will usually reveal the pixel.
Tracking pixels and phishing often travel together, since attackers use them to confirm an inbox is active. Our guide to email security, phishing protection and TLS covers how to spot the dangerous ones.
A note for senders: tracking and privacy law
If you send emails, tracking isn't automatically off-limits, but it isn't a free-for-all either. In the EU and UK, privacy rules such as GDPR and ePrivacy laws are widely interpreted to require consent for tracking technologies like pixels, much like cookies. Other regions have their own rules. Be transparent in your privacy policy, track only what you need, and check local requirements with a legal professional. Knowing the difference between transactional and marketing emails also helps, since expectations differ for each.
FAQ
Can someone tell if I opened their email?
Often, yes. If the email contains a tracking pixel and your app loads images automatically, the sender's tool records the open. Blocking remote images stops most of this.
Does Gmail block tracking pixels?
Not by default. Gmail loads images through its own proxy, which hides your IP address and location, but the sender can still see that the email was opened. Turn on "Ask before displaying external images" to block opens being reported.
Does Apple Mail block email tracking?
With Mail Privacy Protection turned on, Apple Mail hides your IP address and preloads remote content, so senders can't reliably tell when, or whether, you opened an email.
Are tracking pixels dangerous?
They aren't malware and can't access your device. The risk is privacy: they reveal your activity and confirm your address is active, which spammers and phishers value.
Do tracking pixels work in plain-text emails?
No. Plain-text emails can't contain images, so there is nothing to load.
Is email tracking legal?
It depends on where you and your recipients are. In the EU and UK, consent is generally expected for tracking pixels. This isn't legal advice, so check the rules that apply to you.
Does blocking images stop link tracking?
No. Clicking a tracked link still tells the sender you clicked. Type addresses manually if you want to avoid it.
Email that respects your privacy
Blocking pixels protects you from senders. Your email provider matters just as much. NevTan Mail is secure business email built around privacy: no ads, end-to-end and zero-access encryption designed so NevTan can't read your encrypted mailbox, TLS on every connection, two-factor authentication with security keys, and Sentinel monitoring for suspicious account activity. Learn more on our security page.
Weighing your options? See how NevTan compares as a Gmail alternative for business or a Proton Mail alternative, check business email pricing, or start with free business email on your own domain.
