Self-hosted / open sourceBrowserHeadquarters: DE

SeaMonkey: sovereignty score and 8 European alternatives

SeaMonkey is a free internet suite that combines a web browser, a mail and newsgroup client with a feed reader, an HTML editor, the ChatZilla IRC client and developer tools. The browser uses the same rendering engine as Firefox. SeaMonkey continues the product line once made popular by Netscape and Mozilla and runs as a local desktop application on Windows, macOS and Linux; it needs no cloud service from the vendor.

The project is a community effort. The SeaMonkey Association (SeaMonkey e.V.), a non-profit German registered association, hosts the project and provides legal protection. The source code is licensed under the Mozilla Public License 2.0, while the released installation packages are distributed under a separate SeaMonkey end-user licence agreement. Because the software runs locally and is maintained from within the EU, US jurisdiction over the vendor does not come into play. The project itself notes that some websites do not work properly because they support only the latest versions of Chrome or Firefox.

See the 8 European alternatives ↓Assess your stack with SeaMonkey pre-selected

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Sovereignty score

94 / 1000 = high exposure
100 = sovereign

Jurisdiction SOV-2100
Headquartered in the EU: European law applies
Data residency SOV-3100
EU-only hosting
Cryptographic key sovereignty SOV-390
Self-hostable: encryption keys under your own control
Freedom from lock-in SOV-680
Open source: low switching costs
Source & runtime sovereignty SOV-4 · SOV-6100
Source code auditable, forkable and self-hostable

SOV codes: the matching objective in the European Commission's Cloud Sovereignty Framework. Official source

How the score is calculated

Facts and evidence

Last checked October 10, 2026

Headquarters	DE (EU)Verified by hand
Sovereignty model	Open-source, distributedVerified by hand
Data hosting	EUVerified by hand
Open-source	YesVerified by hand
GDPR-compliant	YesVendor-stated
Category	Browser
Type	Product
Website	seamonkey-project.org ↗

How we verify · Something wrong? Suggest a correction

Top EU-based & GDPR-compliant alternatives to SeaMonkey

The European alternatives to SeaMonkey come from our knowledge base of over 6,800 vendors. We only list vendors headquartered in the EU or the EEA; fully European-owned vendors rank before vendors with a foreign owner. For each alternative you see the country, the open-source status and a short description.

Score per alternative: 0 = high exposure, 100 = sovereign

18 European Browser vendors are in the catalogue. View the whole category · Submit an alternative · View category on the map

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Why digital sovereignty matters with SeaMonkey

SeaMonkey is headquartered in DE and therefore falls under European law: the GDPR, NIS2 and the Data Act. No foreign legislation can compel access to your data.

Data is hosted exclusively in the EU, so SeaMonkey scores best on data residency.

SeaMonkey is open source. You can audit the source code, self-host the software and keep the encryption keys under your own control. Switching is easier because data and software are not tied to a single party.

What this means for your organisation depends on your whole stack and context. The free assessment weighs SeaMonkey together with your other vendors and gives a total score, a heatmap and the main risk drivers.

Frequently asked questions

What is the best European alternative to SeaMonkey?

It depends on your use case. Strong EU alternatives to SeaMonkey include Ecosia Browser, Falkon and Iridium Browser. On this page you can compare 8 EU alternatives by jurisdiction, data residency and open-source status.

Are there open-source alternatives to SeaMonkey?

Yes. Open-source EU alternatives to SeaMonkey include Falkon, Iridium Browser, Konqueror, LibreWolf, Midori, Mullvad Browser and Nyxt. These keep your data fully under your own control and let you self-host if you want to.

Is SeaMonkey GDPR-compliant and where is the data hosted?

SeaMonkey is headquartered in DE (EU) and hosts data in EU. It is also open-source, so you can self-host it. That makes SeaMonkey an EU-sovereign choice in its own right; the EU alternatives on this page are comparable European tools.

Details and sources

Verified by handHeadquarters, owner, hosting locations and licence have been checked by us against public sources. Free of charge and for every vendor, not a paid label. Nothing in this knowledge base is taken over automatically. Last checked on October 10, 2026.

Sources

Public sources used in the latest check of this record.

Compliance evidence

The links below point to the vendor's own public documents. We only record what we found: a missing link means "not found publicly", not "not compliant".

No public compliance evidence has been recorded for this vendor yet. Do you know its DPA or subprocessor list? Something wrong? Suggest a correction

Cyber Resilience Act

Public signals that relate to the EU Cyber Resilience Act. They do not count towards the score. A missing line means "not found publicly".

We found none of these signals on the vendor's own site when we checked.

For products in scope of the CRA, CE marking is required from 11 December 2027; this cannot be checked yet.

Checked on October 10, 2026. What is the Cyber Resilience Act?

Digital sovereignty in Browser

Browser: Web browser — browsing, privacy, extensions, sync. In this category the choice of vendor determines who has legal access to your data, where that data lives and how easily you can switch later.

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