fingerprint-svelte

name	fingerprint-svelte
description	Integrate Fingerprint device identification into a Svelte / SvelteKit app — initialize the agent and get the visitor's visitor_id and event_id.

Fingerprint — Svelte

Integrate Fingerprint into a Svelte / SvelteKit app to identify visitors: initialize the provider once at startup, then ask it for the visitor's visitor_id and a single-use event_id wherever you need it (on load, or on an action like login or checkout).

Docs: https://docs.fingerprint.com/docs/svelte · JS Agent v4: https://docs.fingerprint.com/reference/js-agent-v4

Package

@fingerprint/svelte — install the latest version. (For plain HTML or an unsupported framework, use @fingerprint/agent instead.)

Env var

• FINGERPRINT_PUBLIC_API_KEY — the public key, safe to ship to the browser.

Bundlers only expose prefixed vars to client code — map the key to the bundler's convention:

• Vite (plain Svelte): VITE_FINGERPRINT_PUBLIC_API_KEY → import.meta.env.VITE_...
• SvelteKit: PUBLIC_FINGERPRINT_PUBLIC_API_KEY → import { PUBLIC_FINGERPRINT_PUBLIC_API_KEY } from '$env/static/public' Only PUBLIC_-prefixed vars reach the browser in SvelteKit. Never expose the secret key.

Steps

1. Install @fingerprint/svelte.

2. Initialize once at the app root. Wrap the app in FingerprintProvider, passing an options object with the public key and region (us | eu | ap, matching the workspace). The Svelte provider takes a single options prop. See snippets/Provider.svelte.

3. Get the identification where you need it. Use useVisitorData. For identify-on-demand pass { immediate: false } and call getData() on the action you care about; it returns { visitor_id, event_id, ... }. See snippets/CreateAccountForm.svelte.

4. Verify it works. Disable your ad blocker, run the dev server, trigger the call, and confirm a visitor_id is logged in the browser console (or that the event appears on the dashboard Events page).

Notes

• Region must match the workspace (us | eu | ap).
• Initialize once at the app root; don't re-instantiate per component. Don't block the UI on identification — handle the isLoading / error states.
• Production: protect the agent from ad blockers with a custom subdomain or proxy — https://docs.fingerprint.com/docs/protecting-the-javascript-agent-from-adblockers.
• Don't use legacy @fingerprintjs/fingerprintjs-pro, FingerprintJS.load(), or scriptUrlPattern.