What Waterfox actually does
Waterfox is an independent web browser built on the same Gecko engine and source code as Firefox, maintained by BrowserWorks Ltd, a small software company registered in London. It was originally created in 2011 by Canadian developer Alex Kontos to offer official 64-bit support back when Firefox was still 32-bit only, and it has since grown into a full alternative browser with its own release cadence, its own default settings and its own visual identity, while still inheriting Firefox's compatibility with most Firefox extensions.
The core product
The pitch is simple: take Firefox's rendering engine and extension compatibility, then change the defaults so nothing is collected and nothing looks like stock Firefox unless you want it to. Telemetry, crash reporting pings and usage statistics are disabled from the first launch rather than requiring a settings hunt. On top of that, Waterfox bundles a native ad and tracker blocker so pop-ups, overlay ads and third-party trackers are stopped without installing uBlock Origin or similar separately, and it supports DNS over Oblivious HTTP, a protocol that splits the job of knowing who you are from the job of resolving what site you're visiting, so no single relay operator can link the two. Customization goes deep: tree-style tabs let you nest related tabs hierarchically instead of a flat row, a vertical tab sidebar frees up screen width, and a restored classic status bar shows the destination URL on hover — a small feature Firefox itself dropped years ago that some users specifically miss.
What's new or notable
Waterfox's ownership history is worth knowing before you commit to it. In December 2019, System1 — an advertising company that has described itself as privacy-focused — acquired Waterfox, which triggered concern in the privacy community about a browser built to block trackers being owned by an ad business. That concern eased in July 2023, when Kontos announced Waterfox had been spun back out as an independent project. Since then, the team shipped a proper Android app through Google Play in November 2023, and in April 2025 launched a companion privacy-oriented metasearch engine, extending the product beyond just the browser shell. That tool, Waterfox Private Search, entered open beta on April 30, 2025, and treats every query as if it came from a fresh, anonymous device rather than tying it to a persistent profile — the announcement describes each search as "completely fresh, as if it were coming from a new device." The beta currently returns results from Google under the hood, though the team has said it plans to let users switch between backend search engines over time, and the interface deliberately skips AI-generated answer summaries that would otherwise pull clicks away from the original source sites, pairing that with domain blocklists, adjustable link-preference settings and a choice of interface themes.
Who should use Waterfox
Great fit if…
- You like Firefox's engine but not its telemetry defaults — Waterfox keeps Firefox-level compatibility while disabling data collection from the start.
- You're a heavy tab hoarder — tree tabs and the vertical sidebar are built for people who routinely run 40+ open tabs and need structure, not a flat list.
- You want ad blocking without configuring an extension — the built-in blocker works immediately after install.
- You'd like a built-in, no-profile search option — Waterfox Private Search treats each query independently rather than building an advertising profile from your search history.
Skip it if…
- You're on iPhone — there is no iOS build, so mobile parity only exists on Android.
- You rely on niche Firefox extensions — most work, but Waterfox's smaller team patches compatibility issues more slowly than Mozilla does after major engine updates.
Pricing in detail
Waterfox has no paid tier, no premium unlock and no account requirement. Every feature described above — ad blocking, DNS over Oblivious HTTP, tree tabs, themes — is included in the single free download for every supported platform.
| Plan | Price | What's included |
|---|---|---|
| Waterfox | Free — €0 | Full browser, ad/tracker blocking, DNS over Oblivious HTTP, tree tabs, all themes, Windows/macOS/Linux/Android |
Where it falls short
- No iOS app — Apple's engine restrictions and a small team combine to leave iPhone users out.
- Past ownership by an ad company — the 2019–2023 System1 period is a legitimate reason for cautious users to watch the project's governance going forward, even though it's now independent again.
Privacy & data
BrowserWorks Ltd states plainly that Waterfox collects no telemetry and sends no usage data back to the company by default. The bundled ad/tracker blocker prevents third-party scripts from loading in the first place, and DNS over Oblivious HTTP separates query content from requester identity at the network level. There is no Waterfox account system tied to browsing activity. The same no-profile philosophy carries over to Waterfox Private Search: because each query is handled as if it came from a brand-new device, there's no accumulating search history for the company, or anyone else, to build a targeting profile from.
How we checked this
Verified directly against waterfox.com, BrowserWorks Ltd's UK company filing on Companies House (company number 14843353, registered in London), and the English Wikipedia article on Waterfox for the System1/independence timeline, all checked 2026-09-05.
What you get, what you give up
What you get
- Telemetry and data collection are disabled out of the box, not opt-out — nothing is sent to BrowserWorks by default
- Built-in ad/tracker blocking and DNS over Oblivious HTTP ship natively, without needing three separate extensions to match
What you give up
- No dedicated iOS build exists, so iPhone users can't get the desktop feature set on mobile
- A much smaller team than Mozilla's means slower patching of edge-case extension incompatibilities after major Gecko updates