Pixel trackers can hide in your email images
All those obnoxious marketing emails that crowd your inbox are just not promoting a product. They’re also tracking whether you’ve opened the email, when you opened it, and where you were at the time, using software like Mailchimp to embed tracking software into the message.
how does it work? A single tracking pixel is embedded in the email, usually (but not always) hidden within an image or link. When the email is opened, the code within the pixel sends the information back to the company’s servers.
There have been some attempts to limit the amount of information that can be transmitted in this way. For example, since 2014, Google renders all images in Gmail through its own proxy server, which can hide your location from at least some tracking applications. and extensions like ugly email and pixelblock Developed to block trackers on Chrome and Firefox.
There’s also a simple, basic step you can take to avoid trackers: prevent your email from loading images automatically, because images are where most of these pixels hide. You won’t be able to avoid all the trackers that may be hiding in your email this way, but you will stop many of them.
Here’s how to disable image autoloading in the major desktop and mobile email apps:
gmail on the web
- Click the gear icon in the upper-right corner to access your settings, and then click “See All Settings.”
- In the “General” tab (the first one), scroll down to “Images”.
- Select “Ask before displaying external images”.
- Scroll to the bottom of the page and click “Save Changes”.
Note that this will also turn off Gmail’s dynamic email feature, which makes email more interactive.
While the browser-based version of Outlook doesn’t let you stop loading images, you can let it load images through its own service. To enable it:
- Click “Settings” (the gear symbol in the upper-right corner). In the column that opens, click “View all Outlook settings” at the bottom.
- Select “General” > “Privacy & Data”.
- Scroll down to “External images” and select “Always use Outlook service to load images”.
Microsoft Outlook for Windows 10 (Office 365)
- Click “File” > “Options”.
- In the “Outlook Options” window, select “Trust Center.”
- Click the “Trust Center Settings” button.
- Check the boxes labeled “Do not automatically download images in standard HTML email messages or RSS items” and “Do not download pictures in encrypted or signed HTML email messages.” You can make several exceptions, if you wish, by reviewing the boxes below the first item.
Mac. for Microsoft Outlook (Office 365)
- Go to “File” > “Preferences” > “Reading”.
- You can choose to automatically download images only from trusted contacts, or to disable all automatic downloads of images.
- Select “Mail” > “Preferences”.
- Click on the “view” tab.
- Uncheck “Load remote content in messages”.
gmail for android
- Tap on the three lines in the upper-left corner.
- Scroll down and select “Settings”.
- Tap on the email account you want to configure.
- Scroll down and select “Images”.
- Tap “Ask before displaying external images”.
gmail for ios
- Open Gmail for iOS, tap the hamburger menu in the top left, and scroll down to Settings.
- Tap the account you want to personalize, and tap “Images.”
- Switch from “Always display external images” to “Ask before display external images”.
Apple Mail for iOS
- Tap on “Settings” > “Mail”.
- Find the “Messages” section and toggle off “Load remote images”.
Another option is to use an email client such as thunderbird, which by default blocks remote images; The app allows you to download embedded content on an individual basis, or to allow pictures from contacts you trust not to send hidden codes to their images.
Update July 3rd, 2019, 3:47 PM ET: This article has been updated to include additional information about email clients.
Update September 3, 2019, 7:35 p.m. ET: This article has been updated to include instructions on how to disable image autoloading on Gmail for iOS.
Update February 17th, 2021, 5:30PM ET: Instructions for Microsoft Mail have been removed, and some instructions have been updated.
Update June 11, 2021, 8:00AM ET: Instructions have been added for Outlook.com and Outlook for Mac, and some other instructions have been updated.