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early access

Know what your ad blockers are hiding from your analytics.

A tiny client library that measures the per-provider block rate of the third-party tools your app depends on. Drop it in, see exactly how much PostHog, Optimizely, GA4 and friends are costing you.

Try the live demoGet a hosted accountView on GitHub

Right now, 53.3% of checks are blocked on average across 10 providers.

app.tsx
1import { BlockRate, serverReporter } from "blockrate";
2
3new BlockRate({
4  providers: ["optimizely", "posthog", "ga4"],
5  service: "web-app",
6  reporter: serverReporter({
7    endpoint: "https://blockrate.app",
8    apiKey: process.env.NEXT_PUBLIC_BR_KEY!,
9  }),
10}).check();

Per-provider, not "is there a blocker"

Block rate is checked per service. Optimizely might be blocked while PostHog gets through. Other libraries only tell you whether ANY blocker exists.

First-party, not third-party

Bundles into your own code. Under 2 KB gzipped. The detection script itself can’t be blocked because it isn’t served from a third-party CDN.

Honest about the gap

See the exact percentage of users who can’t reach each tool, sliced by browser family. No fingerprinting, no personal data.