[opensourcedex]

best-of ranking · updated nightly

Best Open Source Data Security & Privacy Tools

Ranked by GitHub stars — actual adoption, not editorial taste. All 10 are free, open source and self-hostable; license and last activity on every entry.

  1. 1
    Puter ★ 44K

    A full desktop environment that runs in your browser

    AGPL-3.0 TypeScript pushed 2026-09-17 details →
  2. 2
    Mattermost ★ 39K

    Secure collaboration platform for mission-critical work

    NOASSERTION TypeScript pushed 2026-09-17 details →
  3. 3
    Signal ★ 29K

    Private messaging with end-to-end encryption

    AGPL-3.0 Kotlin pushed 2026-09-17 details →
  4. 4
    Ente ★ 29K

    Secure, private photo storage and sharing solution

    AGPL-3.0 Dart pushed 2026-09-17 details →
  5. 5
    Element ★ 13K

    Secure, decentralized messaging for teams and individuals

    AGPL-3.0 TypeScript pushed 2026-09-17 details →
  6. 6
    Fluxer ★ 10K

    Open source messaging with privacy and community focus

    AGPL-3.0 TypeScript pushed 2026-09-17 details →
  7. 7
    Tuta ★ 7.9K

    Secure email, calendar and contacts with end-to-end encryption

    GPL-3.0 TypeScript pushed 2026-09-17 details →
  8. 8
    Zen ★ 4.2K

    System-wide ad-blocking and privacy protection, no extensions needed

    MIT Go pushed 2026-08-28 details →
  9. 9
    Cinny ★ 3.9K

    Secure and elegant Matrix client for seamless conversations

    AGPL-3.0 TypeScript pushed 2026-09-15 details →
  10. 10
    Stoat ★ 3.3K

    Group chat for friends and communities, without the baggage

    NOASSERTION Rust pushed 2026-09-17 details →
method stars desc · snapshot from github api refresh nightly related Identity & Access Management (IAM), Network Security, Threat Detection & Response, Secrets Management, Application Security, Fraud Prevention

Related best-of lists

best Identity & Access Management (IAM) →best Network Security →best Threat Detection & Response →best Secrets Management →best Application Security →best Fraud Prevention →

last updated nightly · ranking method: github stars, live-tracked

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Frequently asked questions

What is the best open source Data Security & Privacy tool in 2026?

Puter leads the ranking with 43,557 GitHub stars, ahead of Mattermost. Rankings use live GitHub star counts, refreshed nightly.

How is this list of Data Security & Privacy tools ranked?

By GitHub stars — a proxy for adoption and community size. Each entry also shows its licence, primary language and last commit date, so you can judge maintenance activity rather than trusting the ranking alone.

Are the best Data Security & Privacy tools free?

Every project on this list is open source and free to self-host. Some also offer paid managed hosting, but the software itself carries no licence fee.