NOTIFI.CHECK / GUIDE
FCM vs OneSignal: Which Should You Test With
Firebase Cloud Messaging (FCM) and OneSignal both deliver push notifications to Android, iOS, and web — but they differ in credential model, targeting, and what's built on top. Here's how they compare.
| FCM | ONESIGNAL | |
|---|---|---|
| Credential model | Firebase service account JSON (project-scoped admin credential) | App ID + REST API key (no per-project file to manage) |
| Targeting | Raw device/web-push registration token, or topic/condition | Player ID / Subscription ID, or segments and tags |
| Delivery infra | Google's own infra — direct to Android, iOS (via APNs), and web push | Third-party layer on top of FCM/APNs — adds its own dashboard, analytics, A/B testing |
| Setup cost | Requires a Firebase project + generating a service account key | Requires a OneSignal account + linking your Firebase/APNs credentials once |
| Best fit | You already run on Firebase, or want the fewest moving parts / vendors | You want built-in segmentation, A/B testing, and analytics without building it yourself |
Can I use both FCM and OneSignal in the same app?
Yes — OneSignal actually sends through FCM/APNs under the hood for many platforms, so using OneSignal doesn't require you to give up Firebase. Some teams use FCM directly for transactional pushes and OneSignal for marketing segments.
Which is free?
Both have generous free tiers for testing and small-to-medium volume. FCM is free at any volume for standard messages. OneSignal is free up to a subscriber-count threshold, then paid tiers add advanced segmentation and support.
Which is easier to test without writing code?
Both — Notifi Check supports sending a real test push through either provider directly from the browser: FCM via a service account JSON, or OneSignal via an App ID and REST API key.