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Clear out junk files and repair common Windows errorsFree Scan →Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →For fewer email-open signals, choose based on how remote content is handled: Proton Mail says it filters known tracking pixels and loads remote images through a proxy, while Tuta blocks external images by default until you allow them. Proton favors image convenience; Tuta favors a stricter block-by-default setting. Neither should be treated as a guarantee against every way an email can signal that it was opened.
How the main options handle email tracking
| Option | Remote-content approach | Best fit | Tradeoff |
|---|---|---|---|
| Proton Mail | Proton says it blocks known tracking pixels and loads remote images through a proxy, limiting what the remote host learns about the reader’s IP address and open. Proton’s comparison describes this approach. | Readers who want remote images to display while reducing known pixel tracking. | Proxying and filtering do not establish protection against every tracking technique. A 2025 study found other vectors in its tested Proton Mail Android configuration. |
| Tuta Mail | Tuta says external images are blocked by default and are not loaded unless the reader permits them. Its security page also describes stripping IP headers. | Readers who prefer external content not to load without an explicit choice. | Messages that rely on remote images may look incomplete until images are allowed. |
| Email alias or masking service | A unique address can conceal your primary address from a signup or sender. The Associated Press names DuckDuckGo Email Protection, Firefox Relay, Addy.io, and SimpleLogin as examples in its guide to decoy addresses. | Reducing exposure of your main address to websites and services. | An alias does not stop remote content inside a message from reporting an open. |
These are different defenses, not a universal ranking. For routine email with images, Proton’s stated proxy-and-filter approach is the more convenient fit. If you would rather decide before external images load, Tuta’s default is the closer match.
Why email-open tracking is not just a pixel
A tracking pixel is a tiny remote image that can tell a sender when a message is opened and, depending on how it is fetched, information such as the recipient’s IP address. But remote images are only one possible mechanism. The authors of the 2025 ACM CCS paper Doubly Dangerous: Understanding the Security Threats of Email Tracking examined eight popular email services and reported tracking signals involving images as well as fonts, audio, video, and CSS.
In their tested default settings, the authors wrote that “all email providers except Tuta Mail leak at least one email open signal to the tracking server, accounting for more than 2 billion users”. That finding applies to the services, clients, vectors, and defaults evaluated in that study; it is not a guarantee about every current app version, account configuration, or message.
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What the study means for Proton users
The study did not find regular <img> pixel leakage in the tested Proton Mail Android client, but did report leaks through certain <picture> and CSS-background vectors. This is a specific result for that client and evaluation, not proof that all Proton clients behave the same way or that every current message can be tracked.
What the study means for Tuta users
Tuta was the only examined service for which the researchers did not report an email-open signal leak under their tested defaults. That supports its stricter default as a useful choice, but the result should still be read within the study’s scope rather than as a promise that tracking is impossible in all circumstances.
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Choose by image convenience, client, and migration needs
- Choose Proton if you want remote images to remain visible while the service filters known pixels and fetches images through its proxy. Review the specific mail app and device you plan to use; protection can differ by client and tracking vector.
- Choose Tuta if you want external images to stay blocked unless you actively permit them, and are willing to reveal images selectively when a message needs them.
- Add an alias if your goal is to keep your primary address off sign-up forms or limit address-based spam correlation. Treat it as address privacy, not a replacement for remote-content controls.
- Check before switching that your existing accounts, contacts, and preferred email clients fit the provider’s available workflows. The tracking evidence alone does not establish which service will best fit a particular migration.
Anti-tracking and encryption protect different things
Remote-content controls concern signals that can be sent when a message is opened. Encryption concerns who can read message content and under what circumstances; the labels “encrypted” and “private” do not by themselves tell you whether a remote resource will load or what it can reveal.
Tuta says it encrypts email, calendar, and contacts by default and generates keys locally; details are on its security page. Proton describes end-to-end and zero-access encryption for covered content in its Mail security information. Those claims should not be generalized to every message exchanged with every outside recipient.
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Proton’s Mail privacy policy says unencrypted incoming messages from external providers and outgoing messages to external non-Proton services may be scanned for spam and viruses before encrypted storage. That is a separate issue from whether a message loads remote tracking content.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Prices and plan limits
Exact current prices and tier limits are not established here, so a numeric comparison would risk being misleading. Check each provider’s official plan page for current regional pricing, included storage, and feature limits before choosing.
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