Firebase FCM vs OneSignal
Compare Firebase FCM and OneSignal based on observed push API performance and features
Live performance comparison
Real-world performance data from notifications sent through Knock
| Provider | Notification volume | Growth | Status page updates (30d) | Status page updates (90d) |
|---|---|---|---|---|
| 25M–100M | 1st of 5 → | 0 | 2 |
| <1M | 5th of 5 → | 5 | 16 |
From January 22nd to April 22nd, Knock routed 25M–100M notifications through Firebase FCM and <1M through OneSignal. Firebase FCM reported 2 status page updates over the last 90 days, while OneSignal reported 16.
Response time
Response time measures how long each provider takes to accept a push API request from Knock, including connection overhead and any automatic retries. Lower values mean faster notification hand-off.
| Provider | Median (p50) | p90 | p95 | p99 |
|---|---|---|---|---|
| 79ms | 149ms | 171ms | 296ms |
| 225ms | 334ms | 389ms | 545ms |
The chart above shows each provider's daily median response time (p50) from January 22nd to April 22nd. The top-line number is an average of these daily values: Firebase FCM averaged 79ms compared to 225ms for OneSignal. Firebase FCM's highest daily p50 was 97ms; OneSignal's was 240ms. Firebase FCM is 146ms faster at the median, which can add up at high volumes.
The 90th percentile (p90) captures the slowest 10% of requests, revealing how each provider handles moderate stress. Averaged across all days, Firebase FCM has a p90 of 149ms compared to 334ms for OneSignal. The highest daily p90 was 158ms for Firebase FCM and 401ms for OneSignal. Firebase FCM handles these slower requests 185ms faster, suggesting more consistent performance across the board.
The 99th percentile (p99) represents the long tail — the slowest 1% of requests. Averaged across all days, Firebase FCM reached 296ms at p99 while OneSignal reached 545ms. The highest daily p99 was 350ms for Firebase FCM and 15133ms for OneSignal, indicating the worst-case response time during spikes or provider-side congestion. Firebase FCM shows a tighter tail, which may matter for time-sensitive push notifications like real-time alerts where even rare delays can impact user experience.
Error rate
Error rate tracks the ratio of 5xx responses and timeouts to total push API requests. Knock automatically retries failed requests, so transient provider errors rarely affect end-user delivery.
| Provider | Avg. daily error rate | Highest daily rate | Peak error date | Zero-error days | Days above 0.01% |
|---|---|---|---|---|---|
| 0.03% | 0.08% | Feb 3 | 13 | 56 |
| 0.13% | 2.88% | Apr 13 | 81 | 7 |
Averaged across the date range, Firebase FCM shows a 0.03% daily error rate compared to 0.13% for OneSignal. The highest single-day error rate was 0.08% for Firebase FCM and 2.88% for OneSignal. Firebase FCM demonstrates a lower error rate, indicating slightly more consistent availability during this period. Knock automatically retries failed requests to both providers, minimizing the impact of transient errors on end-user delivery.
About these metrics: Data represents notifications sent through Knock during the specified period. Response time measures time from Knock to provider acceptance. Error rate includes only provider 5xx responses and timeouts.
Recent Firebase FCM incidents
Recent status page incidents for Firebase FCM
Started Mar 17, 2026 — Resolved Mar 17, 2026
404 error for Firebase Cloud Messaging clients sending to a URL with a trailing slash
Started Mar 8, 2026 — Resolved Mar 31, 2026
Minor Intermittent Latency Increases for Some Firebase Cloud Messaging Services
Recent OneSignal incidents
Recent status page incidents for OneSignal
Started Apr 13, 2026 — Resolved Apr 13, 2026
Status: Resolved Incident is resolved. Affected components Dashboard / UI (Operational) Email (Operational) SMS (Operational) In-App Messages (Operational) Push (Operational)
Started Apr 9, 2026 — Resolved Apr 9, 2026
Status: Resolved The issue has been resolved. All impacted systems are now operating normally. Affected components Analytics & Reporting (Operational) Dashboard / UI (Operational)
Started Apr 9, 2026 — Resolved Apr 9, 2026
Status: Resolved The issue has been resolved. All impacted systems are now operating normally. Affected components Dashboard / UI (Operational) APIs & SDK Endpoints (Operational)
Started Apr 9, 2026 — Resolved Apr 9, 2026
Status: Resolved The issue has been resolved. All impacted systems are now operating normally. Affected components Dashboard / UI (Operational) APIs & SDK Endpoints (Operational)
Started Apr 1, 2026 — Resolved Apr 1, 2026
Status: Resolved Our engineering team identified the issue internally and has completed the necessary mitigation and resolution steps. Affected components In-App Messages (Operational) Journeys (Operational) Push (Operational) Dashboard / UI (Operational) Email (Operational) Integrations (Operational) APIs & SDK Endpoints (Operational) SMS (Operational) Analytics & Reporting (Operational)
Pros and cons
Firebase FCM
OneSignal
Pros
- Free with no per-notification cost at any volume
- Cross-platform support for Android, iOS, and web from a single API
- Deep integration with the Firebase ecosystem including analytics and remote config
- Topic and device group messaging simplifies broadcasting to subscriber segments
Pros
- Generous free tier with unlimited mobile push makes it accessible for small teams and hobby projects
- Visual editor and prebuilt UI enable non-technical teammates to compose, target, and schedule campaigns
- Broad channel coverage including push, email, SMS, and in-app messages from a single platform
- Fast to get started with SDKs, guided setup, and strong documentation
Cons
- iOS delivery still routes through APNS, adding a layer of indirection
- Payload size limited to 4KB, which can be restrictive for rich content
- Firebase console UI can be complex for teams not already using Firebase
Cons
- Workflow builder is tuned for marketing campaigns and lacks granular, event-driven control for transactional product messaging
- Subscription and tag-based preferences model is less flexible than a user-and-channel preference model for complex cross-channel logic
- Separated environments for development, staging, and production aren't first-class, which can complicate team workflows
- End-to-end observability and message-level debugging is more limited than dedicated notification infrastructure platforms
Frequently asked questions
What is the difference between Firebase FCM and OneSignal?
Firebase Cloud Messaging (FCM) is Google's free, cross-platform push notification service supporting Android, iOS, and web with topic messaging and analytics integration. OneSignal is a cross-platform push notification service with built-in segmentation, A/B testing, analytics, and intelligent delivery optimization. Firebase FCM is best suited for cross-platform android and web notifications, while OneSignal is geared toward cross-platform push with built-in analytics.
Which is cheaper, Firebase FCM or OneSignal?
Firebase Cloud Messaging is free to use with no per-notification cost. Google does not charge for message delivery regardless of volume. FCM is included in all Firebase plans, including the free Spark plan. OneSignal offers a free tier for up to 10,000 subscribers. Growth plans start at $9/month with additional subscribers and features. Professional plans start at $99/month with advanced analytics, in-app messaging, and journeys. Enterprise pricing is custom. The best value depends on your sending volume and target platforms.
Which is faster, Firebase FCM or OneSignal?
Based on real-world data from Knock, Firebase FCM has a median push API response time (p50) of 79ms compared to 225ms for OneSignal.
Which is more reliable, Firebase FCM or OneSignal?
From January 22nd to April 22nd, Firebase FCM showed an error rate of 0.03% while OneSignal showed 0.13%. Both rates are within acceptable thresholds for production push notification delivery, and Knock automatically retries failed requests to minimize the impact of transient errors.
Which is more popular, Firebase FCM or OneSignal?
On the Knock platform, Firebase FCM handled 25M–100M notifications from January 22nd to April 22nd compared to <1M for OneSignal. Firebase FCM volume has remained stable, while OneSignal volume has remained stable.
Can I use both Firebase FCM and OneSignal together?
Yes. Knock enables you to integrate multiple push notification providers into a single notification workflow. You can use Firebase FCM and OneSignal side by side, route traffic between them, or migrate from one to the other without changing your application code.
What are the main pros and cons of Firebase FCM vs OneSignal?
Firebase FCM strengths include free with no per-notification cost at any volume and cross-platform support for android, ios, and web from a single api. OneSignal strengths include generous free tier with unlimited mobile push makes it accessible for small teams and hobby projects and visual editor and prebuilt ui enable non-technical teammates to compose, target, and schedule campaigns. On the other hand, Firebase FCM drawbacks include ios delivery still routes through apns, adding a layer of indirection, while OneSignal drawbacks include workflow builder is tuned for marketing campaigns and lacks granular, event-driven control for transactional product messaging.
Use either provider with Knock
Knock enables you to integrate Firebase FCM, OneSignal, or any combination of push notification providers into a single notification workflow. Manage templates, orchestrate cross-channel delivery, and switch providers without changing your code.