FingerprintJS alternative: server-side device ID and abuse checks
Updated
The open-source FingerprintJS library computes a browser fingerprint in the page, which is useful for analytics but can be forged by anyone who controls the browser. For abuse prevention you need the ID computed and matched on a server and a decision your backend can trust. FingerPrint Checker collects signals in the browser, Android and iOS, matches them on its server and answers allow, deny or a human check for trials, coupons and referrals.
What is FingerprintJS?
FingerprintJS is a widely used open-source JavaScript library. It reads browser signals such as canvas, audio, fonts and screen properties and hashes them into a visitor identifier inside the page. Its maker also sells a commercial service that identifies visitors on its own servers.
Developers usually look for an alternative when they need the ID to hold up against abuse, need it in mobile apps as well, or want a ready answer to "has this device already claimed the offer?" rather than an ID to build rules around.
Client-side fingerprint versus server-verified device ID
A client-side library hashes signals in JavaScript and hands the ID to your code. Because the hash is computed where the user has control, a script can replay or invent IDs, and the ID changes whenever any input changes.
A server-verified ID is different: the browser only uploads raw signals in a sealed request with a one-time nonce. The server recomputes every hash, fuzzy-matches against known devices so small browser changes keep the same ID, and signs the result so it cannot be altered on its way through your backend.
What to compare when choosing an alternative
- Where the ID is computed: in the page or on the server.
- Matching: exact hash or per-signal fuzzy matching that survives browser updates.
- Platforms: browser only, or native Android and iOS with platform attestation.
- Decisions: an ID you must build rules around, or ready answers for trials, coupons, quotas and referrals.
- Pricing: per request or per decision, and whether there is a free tier without a card.
When an open-source library is enough
If you only need to de-duplicate analytics or remember a preference, an in-page fingerprint library is simpler and free. Once a free offer has real cost, such as a trial, a coupon or a referral bonus, move the decision to the server.
FingerPrint Checker in short
Browser agent plus Android, iOS and macOS SDKs. Server-side hashing, fuzzy matching, a trust score for automation, tampering, datacenter and Tor traffic, and a human check by Cloudflare Turnstile or proof-of-work. You pay per decision with prepaid credits: 2,000 free on sign-up, then $19 for 10,000, $99 for 60,000 or $399 for 300,000 checks, valid for 12 months.
Frequently asked questions
Do I have to remove FingerprintJS to use FingerPrint Checker?
No. They can run side by side. Many teams keep an existing client library for analytics and use FingerPrint Checker only for the decisions that give something away.
Does FingerPrint Checker work in mobile apps?
Yes. Native SDKs for Android, iOS and macOS use hardware identifiers for identity and Play Integrity, App Attest or DeviceCheck for trust.
Try FingerPrint Checker free
Every new account gets 2,000 free checks. No card required to start.
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