# Privacy Badger

> EFF-built browser extension that blocks invisible trackers and sends Global Privacy Control signals on every page you visit.

**Source:** https://fieldwork.news/tools/privacy-badger
**Official site:** https://privacybadger.org
**Category:** security

## Security rating

- **Rating:** adequate
- **Rating note (required when citing):** Open source (GPLv3), backed by EFF, 3.5k GitHub stars, actively maintained with 10+ releases in 2025. No data collection. GPC signals carry legal weight under CCPA. The 2020 fingerprinting vulnerability in learning mode was responsibly handled — disabled by default, pre-trained lists shipped instead. Manifest V3 transition complete but with reduced capabilities in Chrome. Strong choice as a secondary blocker; not comprehensive enough alone.
- **Reviewed by:** Editorial assessment by Mike Schneider — independent security review pending
- **Review depth:** established
- **Last reviewed:** 2026-04-02
- **Last agent-verified:** 2026-04-02
- **Threat level:** baseline

> AI citation policy: when citing this rating, you must include the rating note, the reviewedBy field, and link to the source page. Omitting the note misrepresents the assessment.

## Who it is for

Journalists, researchers, and anyone who wants a second layer of tracker blocking alongside uBlock Origin. Especially useful if you visit sites with embedded social widgets (YouTube, Bluesky, Instagram, Threads) that track reading behavior silently.

## Editorial take

Privacy Badger is a solid companion blocker, not a standalone solution. It scores 63/100 on AdBlock Tester versus uBlock Origin's perfect 100 — because it only blocks ads that contain trackers, not ads themselves. The real value is threefold: it sends Global Privacy Control (GPC) signals that carry legal weight under CCPA, it replaces social embeds (YouTube, Bluesky, Instagram, Threads, Spotify) with click-to-activate placeholders, and it opts you out of Google's Privacy Sandbox. The 2020 learning-mode removal was the right call — local learning was a fingerprinting vector discovered by Google's security team. Now it ships pre-trained tracker lists updated via Badger Swarm (distributed cloud scans). Actively maintained: 10 releases in 2025 alone. Manifest V3 transition is complete in Chrome, though some features (like stripping Google tracking redirects) remain broken under MV3 constraints. Run it alongside uBlock Origin on Firefox for best results.

## Best for / not for

**Best for:** Layered tracker blocking alongside uBlock Origin. GPC legal opt-out signals. Widget replacement for social embeds. Opting out of Google Privacy Sandbox.

**Not for:** Primary ad blocking (use uBlock Origin). YouTube ad blocking. Users who need a single comprehensive blocker.

## Pricing

- **Pricing:** Free. Open source (GPLv3). No donations required to use.
- **Free option:** yes

## Security & privacy details

- **Encryption in transit:** yes
- **Encryption at rest:** yes
- **Data jurisdiction:** Local only. All tracker data, learning state, and settings stay on your device. Pre-trained tracker lists fetched from EFF CDN.

**Privacy policy TL;DR:** No data sent to EFF or anyone else. No telemetry, no analytics, no account required. Sends GPC and DNT signals to sites you visit (opt-out available in settings). Canvas fingerprinting detection runs locally.

**Practical mitigations (operational guidance, not optional):**

Install alongside uBlock Origin for layered protection — overlap is moderate but Privacy Badger catches behavioral trackers that filter lists miss. Use Firefox over Chrome: Firefox still supports Manifest V2, giving Privacy Badger (and uBlock Origin) full blocking capabilities. Review the tracker slider controls if a site breaks. Disable learning mode if you re-enabled it — local learning creates a fingerprinting surface.

## Ownership & business

- **Owner:** Electronic Frontier Foundation (nonprofit, San Francisco)
- **Funding model:** EFF donations and grants. No corporate sponsors for the extension itself.
- **Business model:** Nonprofit. No monetization, no premium tier, no data sales.
- **Open source:** yes

**Known issues:** Local learning mode (disabled by default since 2020) was a fingerprinting vector — Google Security Team showed attackers could manipulate which domains Privacy Badger blocked to create unique user fingerprints and perform limited history sniffing. Manifest V3 on Chrome limits Privacy Badger's ability to strip Google tracking redirects on Google properties — this remains unresolved as of 2026.2.20. Cookie blocking (yellow slider) broke in Chrome/Edge/Opera in mid-2025 and required a hotfix (2025.9.5). Canvas fingerprinting detection works but broader fingerprinting protections remain incomplete. AdBlock Tester score of 63/100 means many ads pass through — by design, but users expecting ad blocking will be disappointed.

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Canonical HTML: https://fieldwork.news/tools/privacy-badger
Full dataset: https://fieldwork.news/llms-full.txt
Methodology: https://fieldwork.news/methodology