Mastodon vs Bluesky: Privacy Comparison
This in-depth comparison weighs Mastodon against Bluesky along six decisive privacy dimensions: how data is collected, how encryption is implemented, how data is shared with third parties, what privacy controls users get, how transparent each service is, and what their historical track record looks like. The two cover much the same ground, yet they handle user privacy in very different ways. What our review shows is that Mastodon delivers a clearly stronger privacy experience on balance, even though each option has its own relative pluses and minuses that are worth examining closely.
Reading the Scorecard
The most useful starting point is the overall tally and the single dimension that decided it. Across the six privacy dimensions we score, Mastodon finishes ahead of Bluesky, 54/60 to 37/60. That total reflects a side-by-side review in which one service is consistently the more privacy-respecting choice, even though both cover the same functional ground.
Most of the distance between these services opens up on Data Collection: Mastodon 10/10 versus Bluesky 7/10. Encryption is where they come closest, a mere 2-point gap (10 vs 8 out of 10). Everything below justifies these totals dimension by dimension.
What Gets Collected
The starting point for judging privacy is always how data is collected. The amount of user data a service captures, keeps, and works with is the single biggest factor behind its privacy exposure. Mastodon shows more discipline on this front, collecting nothing beyond the bare minimum needed for the service to run. The competing option reaches for a much wider set of data, including behavioral patterns, device identifiers, and usage analytics that stretch beyond the essentials. In this category we rated Mastodon 10/10 and Bluesky 7/10. The gap comes down to more than raw volume -- it is about the intent behind each piece of data and whether collecting it was ever justified.
Encryption Standards
Encryption protects user data both in transit and at rest, and the implementation quality varies dramatically between services. Mastodon implements stronger encryption measures, including more robust protocols for data in transit and better protection for stored data. The specific encryption implementations differ in their coverage (which data is encrypted), their strength (which algorithms and key lengths are used), and whether end-to-end encryption is employed (preventing even the service provider from accessing user content). Mastodon scored 10/10 while Bluesky scored 8/10 for encryption.
Who Else Gets Your Data
How services share data with third parties is a critical privacy dimension. This includes sharing with advertising networks, analytics providers, business partners, and in response to government requests. Mastodon maintains more restrictive policies regarding third-party data access. The data sharing practices affect not just privacy but also the security of user information, as each additional party with access represents a potential breach vector. Scores: Mastodon 7/10, Bluesky 4/10.
What You Can Manage Yourself
Individuals only hold real power over their data when a service's privacy controls are available and genuinely effective. The relevant tools include the option to opt out of data collection, ways to download and erase data, granular permission settings, and how readily users can exercise the rights afforded them by applicable privacy regulations. Mastodon offers more complete and approachable privacy controls. Scores: Mastodon 8/10, Bluesky 5/10.
Transparency
Transparency comes down to how plainly a service explains what it does with data. It shows up in how readable the privacy policy is, whether transparency reports are published, how quickly privacy questions get answered, and whether policy changes are communicated up front. Mastodon comes across as the more transparent of the two overall. Plain, easy-to-find privacy communication is the bedrock of informed consent and trust. Scores: Mastodon 9/10, Bluesky 6/10.
Historical Track Record
A service's history of privacy incidents, regulatory actions, and responses to vulnerabilities provides important context. Mastodon has a stronger historical record on privacy, with fewer incidents and more responsible handling of the issues that have arisen. Past behavior is often the best predictor of future privacy practices. Scores: Mastodon 10/10, Bluesky 7/10.
Overall Verdict
When the full analysis is tallied, Mastodon finishes at 54/60 and Bluesky at 37/60. On privacy grounds, the overall winner is Mastodon. Both products meet similar functional needs, yet the winner brings a more privacy-respecting approach to the dimensions that carry the most weight. Still, perfection is off the table for any service, so no matter which you choose you should actively set up its privacy options. Our advice is to round out your pick with additional privacy tools, a VPN, DNS-level ad blocker, and privacy-focused browser, to assemble a thorough privacy posture. Should your threat model call for the strongest privacy possible, weigh whether an even more privacy-focused alternative exists in this category beyond the two compared here.