FCM & OneSignal Push Notification Tester
Upload your Firebase service account JSON, or paste a OneSignal App ID and REST API key, to send a test push. Credentials are used once per request and never stored on the server.
ABOUT
Notifi Check is a free tool for testing Firebase Cloud Messaging (FCM) and OneSignal push notifications without writing any code. Paste a device or web-push token, upload your Firebase service account JSON — or paste a OneSignal App ID, REST API key, and player ID — and send a real notification straight from the browser. Useful for confirming that a Firebase project, OneSignal app, token, or web-push configuration actually works before wiring it into an app.
WHY TEST DIRECTLY
Push notification bugs are hard to isolate inside a full app — is the token stale, is the service account or REST API key misconfigured, is the payload malformed, or is the push provider itself unreachable? Sending a notification directly, outside your app code, narrows that down in one request. The WEB_PUSH tab also supports a validate-only dry run, so you can check a payload is well-formed without actually delivering it.
HOW IT WORKS
Your Firebase service account JSON is read once from the upload for that single request, used to create a short-lived Firebase Admin instance, and discarded immediately after — it is never written to disk, logged, or stored server-side. Get a service account key from your Firebase project under Project Settings → Service Accounts → Generate new private key — see the step-by-step guide if you need help. For OneSignal, your App ID and REST API key are sent once per request directly to the OneSignal API and never stored — find both under Settings → Keys & IDs in your OneSignal dashboard.