Product review
ThumbmarkJS browser fingerprinting review
ThumbmarkJS combines an open-source browser library with a hosted identification API. The hosted option adds server-side components and a server-generated Visitor ID; it should not be described as only a raw client hash without additional signals.
Editorial score
Open-source collection with hosted identity option
Free access
Open-source library; hosted free tier of 1,000 API calls/month
Paid entry
Pro: 15 euros/month for 15,000 API calls, excluding VAT
Key facts
- Identity and matching scope
- ThumbmarkJS combines an open-source browser library with a hosted identification API. The hosted option adds server-side components and a server-generated Visitor ID; it should not be described as only a raw client hash without additional signals. Vendor page ↗
- Result to inspect
- Local thumbmark or hosted Visitor ID with server signals Vendor page ↗
- Access and pricing
- Open-source library; hosted free tier of 1,000 API calls/month. Pro: 15 euros/month for 15,000 API calls, excluding VAT. 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
- An open-source library makes client collection inspectable.
- The hosted service adds a Visitor ID and server-side components.
- A public demo and free account provide an evaluation route.
Limitations
- The open-source and hosted outputs have different capabilities.
- Confirm hosted pricing, signal fields and behavior on your actual browser mix.
Who it fits
Teams comparing a self-hosted prototype with a hosted visitor-identity option and its operational trade-offs.
Use the alternatives by evidence need to compare overlapping device, identity, behavior and automation capabilities.
What the score means
The 7.2 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.
Live browser demo and free account
Compare the local thumbmark with the hosted Visitor ID and documented additional signals; confirm the selected plan and usage.
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
- Vendor browser-identification articles · checked October 22, 2026
FAQ
What does ThumbmarkJS return?
Local thumbmark or hosted Visitor ID with server signals. ThumbmarkJS combines an open-source browser library with a hosted identification API. The hosted option adds server-side components and a server-generated Visitor ID; it should not be described as only a raw client hash without additional signals.
Who should evaluate ThumbmarkJS?
Teams comparing a self-hosted prototype with a hosted visitor-identity option and its operational trade-offs.
How can I try ThumbmarkJS?
Compare the local thumbmark with the hosted Visitor ID and documented additional signals; confirm the selected plan and usage. Open-source library; hosted free tier of 1,000 API calls/month. Pro: 15 euros/month for 15,000 API calls, excluding VAT.
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