Product review
FingerprintJS (open source) browser fingerprinting review
FingerprintJS is an open-source client-side library that derives a visitor identifier from browser attributes. It is separate from Fingerprint’s hosted identification product: collecting a local identifier does not provide the hosted server matching or entitled Smart Signals.
Editorial score
Self-hosted browser fingerprint library
Free access
Open-source library
Paid entry
No hosted subscription for the library; operating work is yours
Key facts
- Identity and matching scope
- FingerprintJS is an open-source client-side library that derives a visitor identifier from browser attributes. It is separate from Fingerprint’s hosted identification product: collecting a local identifier does not provide the hosted server matching or entitled Smart Signals. Vendor page ↗
- Result to inspect
- Client-generated visitor identifier and components Vendor page ↗
- Access and pricing
- Open-source library. No hosted subscription for the library; operating work is yours. Compare the actual plan, product and usage unit. Vendor page ↗
- Developer evaluation
- Evaluate known repeat visits and different browsers separately. Include cleared storage, privacy settings, browser upgrades, shared devices, missing collection and delayed results. Inspect the returned identifiers and reasons before connecting them to an account action. Vendor page ↗
Strengths
- Source code and API usage are publicly inspectable.
- A local prototype can run without a hosted identification subscription.
- Components can help explain which browser observations changed.
Limitations
- Client-generated output can be modified or replayed and needs a trusted application design.
- Matching persistence, risk enrichment and production maintenance remain separate implementation work.
Who it fits
Teams that want inspectable client collection and can own matching, integrity controls and maintenance.
Use the alternatives by evidence need to compare overlapping device, identity, behavior and automation capabilities.
What the score means
The 7.4 out of 10 score is an editorial assessment under the same 40-criterion, seven-category framework. It weighs identity persistence, evasion resistance, risk evidence, response contracts, developer experience, maintenance and fit.
Editor’s Choice is a separate recommendation. Read all criteria and relative weights and evaluate the entitled product on the product flow you protect.
How to evaluate it
Evaluate known repeat visits and different browsers separately. Include cleared storage, privacy settings, browser upgrades, shared devices, missing collection and delayed results. Inspect the returned identifiers and reasons before connecting them to an account action.
Maintainer’s browser demo
Open the maintainer demo and compare your own permitted browser sessions; keep the open-source output separate from the commercial product.
Open evaluation routeSources and further reading
- Product and detection approach · checked October 22, 2026
- Pricing and access · checked October 22, 2026
- Integration and result documentation · checked October 22, 2026
- Maintainer guide: library scope and limitations · checked October 22, 2026
FAQ
What does FingerprintJS (open source) return?
Client-generated visitor identifier and components. FingerprintJS is an open-source client-side library that derives a visitor identifier from browser attributes. It is separate from Fingerprint’s hosted identification product: collecting a local identifier does not provide the hosted server matching or entitled Smart Signals.
Who should evaluate FingerprintJS (open source)?
Teams that want inspectable client collection and can own matching, integrity controls and maintenance.
How can I try FingerprintJS (open source)?
Open the maintainer demo and compare your own permitted browser sessions; keep the open-source output separate from the commercial product. Open-source library. No hosted subscription for the library; operating work is yours.
Explore checkers, demos and evaluation routes →