Which privacy‑focused search engines in 2025 document zero retention policies, and how do researchers verify those claims?
Executive summary
A set of widely mentioned privacy‑focused search engines—DuckDuckGo, Brave Search, Startpage, Qwant, MetaGer, Searx (and forks), Mojeek and niche players like Gibiru—publicly claim no‑logging or zero data‑retention policies in 2025 according to multiple industry roundups and vendor pages [1] [2] [3] [4] [5] [6] [7]. Researchers verify those claims through document audits (policies and transparency reports), code audits when software is open source, technical network tests and third‑party audits, while also warning that third‑party integrations and regional legal regimes can undercut marketing claims [1] [4] [2] [8].
1. Who in 2025 publicly documents “zero retention” or no‑logging policies
Major consumer guides and vendor statements identify DuckDuckGo as a flagship no‑tracking engine with transparent policies cited in 2025 coverage [1] [9], while Brave Search, Startpage and Qwant are repeatedly listed among top private search options that advertise minimal or no retention of personal search data [2] [5] [6]. MetaGer and Searx (and self‑hosted Searx instances) appear in curated lists as engines that “do not collect or store user data” or are verifiable because their code is open source [3] [4]. Niche players such as Mojeek and Gibiru are also reported in reviews and roundups as offering strict no‑log or no‑IP‑tracking policies [6] [7].
2. What “documented zero retention” typically looks like on paper
Documentation usually takes the form of a published privacy policy stating that queries, IP addresses and search histories are not logged, plus marketing assertions of “zero logging” or “we do not store search data” on product pages [10] [2] [5]. Some vendors supplement policies with transparency reports or blog posts explaining architecture choices—e.g., routing through proxy layers or using an independent index—to argue that IPs cannot be associated with queries [9] [2]. Open‑source projects often add readme files and design documentation so third parties can inspect what data flows might exist [4].
3. How researchers empirically verify “zero retention” claims
Verification layers include: reading and comparing privacy policies and transparency reports for explicit retention limits; reviewing open‑source codebases and deployment configurations to confirm logging paths; running active network captures and browser‑level telemetry to detect outbound identifiers or third‑party trackers; and commissioning independent audits or using regulatory mechanisms (GDPR audits or complaints) to test compliance [1] [4]. Testbeds also use controlled experiments—sending unique, trackable test queries and then requesting data via subject‑access requests where applicable—to see if any logs exist, an approach that academic work on retention policies catalogs as useful for measuring variation in retention behavior [8].
4. Practical tools and signals that bolster verification
Open source is the clearest technical signal because it lets researchers trace code paths for logging and telemetry [4]. Browser extensions and traffic analysis tools such as Privacy Badger or uBlock Origin help detect third‑party trackers and unexpected outbound calls during searches [1]. Using Tor or anonymous proxies while comparing results aids in spotting whether an engine ties IPs to persistent profiles [1] [9]. Finally, independent security reviews, transparency reports, and responses to subject access or data portability requests provide documentary evidence researchers can cite [4] [1].
5. Important caveats, incentives and structural limits
Marketing language and rankings frequently conflate “minimal retention” with “zero retention,” and independent reporting warns that third‑party integrations (analytics, ads, CDN providers) can introduce logs even when the search engine claims none [1] [2]. Legal jurisdiction matters: US companies rely more on internal policy than federal law to avoid retention, while European hosts point to stronger obligations and controls—differences that affect how claims should be read and tested [2]. Academic treatments of data retention emphasize heterogeneity across providers and time, meaning a 2025 claim may be reversible unless paired with external audits or open technical evidence [8].
6. Bottom line
A short list of privacy search engines publicly document no‑logging or zero‑retention stances in 2025—DuckDuckGo, Brave Search, Startpage, Qwant, MetaGer, Searx, Mojeek and similar projects—but rigorous verification requires layered evidence: published policies and transparency reports, open‑source code inspection, active traffic and behavioral testing, subject‑access probes and, ideally, independent audits; absent those, researchers flag third‑party services and jurisdictional rules as plausible routes by which “zero retention” claims can fail to hold up in practice [1] [2] [4] [8].