ChatGPT Atlas Declared Least Private Browser in 2025 Study

A recent report by Digitain has identified ChatGPT Atlas as the least private web browser available in 2025. The browser failed all state partitioning tests, indicating it cannot prevent websites from tracking users across multiple browsing sessions. Despite its popularity, Chrome also scored poorly in privacy, receiving a score of only 41 out of 100 for its ability to secure user connections to websites.

Digitain’s comprehensive browser privacy report evaluated 13 popular browsers based on several security features. Each browser underwent numerous technical tests across three main areas: the ease with which websites can track or identify users, the effectiveness of blocking data collection through cookies and trackers, and the security of connections between websites. The findings resulted in a Privacy Risk Score ranging from 1 to 99, where higher scores imply a greater risk to user privacy.

Privacy Risk Scores Reveal Alarming Findings

According to the report, the ten browsers with the highest privacy risks include:

– ChatGPT Atlas: Privacy Risk Score 100
– Chrome: Privacy Risk Score 76
– Vivaldi: Privacy Risk Score 75
– Microsoft Edge: Privacy Risk Score 63
– Opera: Privacy Risk Score 58
– Ungoogled: Privacy Risk Score 55
– Firefox: Privacy Risk Score 50
– Safari: Privacy Risk Score 49
– DuckDuckGo: Privacy Risk Score 44
– Tor: Privacy Risk Score 40

As detailed in the report, ChatGPT Atlas performed particularly poorly, scoring just 1 point in anti-fingerprinting protection and receiving 0 points for tracker blocking. This indicates the browser does not provide adequate defenses against websites that collect user data via cookies or tracking technologies. Additionally, it scored only 24 out of 100 in connection and navigation security, revealing significant vulnerabilities.

In comparison, Chrome, despite being the most widely used browser globally, earned a Privacy Risk Score of 76. It managed to score 68 in preventing websites from identifying users but received a troubling 0 points for blocking trackers. This allows companies to track user activity freely across the web. Its connection security score of 41 further underscores the browser’s inadequacies in protecting user privacy.

Other Browsers Struggle with Privacy Protection

Following Chrome, Vivaldi ranked third in terms of privacy risk. It matched Chrome’s score of 68 for anti-fingerprinting but, like Chrome, received a 0 for tracker blocking. Its connection security score was slightly lower at 37.

Next in line is Microsoft Edge, which also achieved 68 points for anti-fingerprinting. However, it showed minimal improvement in tracker blocking with a score of 15. Edge’s connection security rating tied with Chrome’s at 41, indicating that while it performed slightly better, it still falls short in providing sufficient privacy protection.

Finally, Opera ranked fifth among the least private browsers. It scored 68 for anti-fingerprinting and 41 for connection security but outperformed Edge, Vivaldi, and Chrome in tracker blocking with a score of 25. Despite these minor improvements, it remains part of a group of browsers that offer inadequate overall privacy protection.

The emergence of AI-powered browsers, such as ChatGPT Atlas and Comet from Perplexity, raises concerns regarding user security. These tools depend on data collection and learning algorithms, potentially gathering more personal information than users are aware of.

The findings from Digitain’s report highlight the pressing need for users to consider privacy when selecting web browsers, particularly if they are concerned about data collection and online tracking.