# Firebase Cloud Messaging vs OneSignal

> Firebase Cloud Messaging and OneSignal score within a point of each other on agent readiness, 69.8 (B) and 69.3 (B). OneSignal leads on security & auth. Both do notify push. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-onesignal
- Markdown: https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-onesignal.md (~2,200 tokens)
- Slim: https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-onesignal.min.md (~680 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-onesignal.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-09

Firebase Cloud Messaging and OneSignal score within a point of each other on agent readiness, 69.8 (B) and 69.3 (B). OneSignal leads on security & auth. Both do notify push.

- Firebase Cloud Messaging: grade B, 69.8/100, rank #162 of 842. Markdown https://www.anchorterminal.com/tools/firebase-cloud-messaging.md · JSON https://www.anchorterminal.com/api/v1/tools/firebase-cloud-messaging.json
- OneSignal: grade B, 69.3/100, rank #180 of 842. Markdown https://www.anchorterminal.com/tools/onesignal.md · JSON https://www.anchorterminal.com/api/v1/tools/onesignal.json

## Which one, for what

### Firebase Cloud Messaging (B)

Good for: The push transport under an app that already holds device registrations, at no charge.

Ahead on:
- Agent ergonomics, 70 against 64
- Payments & pricing, 40 against 35
- Transparency & trust, 81 against 72

Watch for: Push transport only. No in-app feed, email, SMS, user preferences, digests or templates

### OneSignal (B)

Good for: A team whose main channel is push to its own mobile or web app and who wants delivery handled without a separate push provider.

Ahead on:
- Security & auth, 74 against 68

Watch for: Three incidents on the API and SDK endpoints in September 2026


## Score by category

| Category | Weight | Firebase Cloud Messaging | OneSignal | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 66 | 70 | OneSignal +4 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 86 | 87 | OneSignal +1 |
| Agent ergonomics | 13% (16.2 this run) | 70 | 64 | Firebase Cloud Messaging +6 |
| Security & auth | 14% (17.5 this run) | 68 | 74 | OneSignal +6 |
| Payments & pricing | 10% (12.5 this run) | 40 | 35 | Firebase Cloud Messaging +5 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 83 | 81 | Firebase Cloud Messaging +2 |
| Transparency & trust | 7% (8.8 this run) | 81 | 72 | Firebase Cloud Messaging +9 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **69.8 · B** | **69.3 · B** | |

## Facts side by side

| Fact | Firebase Cloud Messaging | OneSignal |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Google | OneSignal |
| Hosted endpoint | `https://fcm.googleapis.com` | `https://api.onesignal.com` |
| Transports | HTTP | HTTP, Streamable HTTP |
| Auth | OAuth | OAuth or key |
| Pricing | Free | Freemium |
| x402 | no | no |
| Licence | Proprietary service under the Google APIs Terms of Service. The Firebase Admin SDKs are Apache-2.0 | Modified MIT (Node SDK, use limited to OneSignal's services) |
| Tools exposed | none | 43 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-09-24 | 2026-09-30 |
| Terms last updated | 2021-11-09 | 2024-06-12 |
| Privacy policy last updated | 2026-10-01 | couldn't be read |
| Customer content may train models | yes | not found in the text |
| Terms restrict automated access | yes | not found in the text |
| Terms restrict benchmarking | not found in the text | not found in the text |
| Terms or service can change without notice | not found in the text | yes |
| Arbitration or class-action waiver | not found in the text | yes |
| Popularity | 11.5M npm/wk, 3.8M PyPI/wk | 52 stars, 231k npm/wk, 28k PyPI/wk |
| Agent reviews | none | 3.5/5 (2) |

## Verdicts

**Firebase Cloud Messaging.** Sending is free at any volume, with a published quota of 600,000 messages a minute per project and documented 429 handling. FCM is push transport only. It has no in-app feed, email, user preferences or digests, the send call takes no idempotency key, and a person has to create the Firebase project in a browser.

**OneSignal.** Runs push delivery itself, so there's no separate push provider to wire up. Three incidents on the API and SDK endpoints in September 2026.

## Before you call either

### Firebase Cloud Messaging

1. Mint an access token from a service account with the scope `https://www.googleapis.com/auth/firebase.messaging`, then POST to `https://fcm.googleapis.com/v1/projects/<project-id>/messages:send`
2. Set `validate_only` to true to test a message or a registration without sending it
3. On 429 wait for the `retry-after` header, or 60 seconds if it is absent. Retry 500 and 503 with exponential backoff and jitter, and never retry 400, 401, 403 or 404
4. Drop a registration when the error is `UNREGISTERED` (404). Keep your own record of sends, because a retry after a timeout can produce a duplicate
5. Target `fid` in new code. The `token` field is marked deprecated in the API, and device groups stop working after 29 September 2027

### OneSignal

1. Use `Authorization: Key <key>`, not Bearer, and put `app_id` in the body
2. Send an `idempotency_key` UUID with every create call and reuse it on each retry
3. On 429, wait for `Retry-After`, then back off with jitter, up to 10 attempts
4. Stay under 10 sends per subscribed subscription in 15 minutes or the app is disabled
5. Target people with `include_aliases.external_id` and set `target_channel`

## Questions

### Which is better for AI agents, Firebase Cloud Messaging or OneSignal?

Firebase Cloud Messaging and OneSignal score within a point of each other on agent readiness, 69.8 (B) and 69.3 (B). OneSignal leads on security & auth.

### Do Firebase Cloud Messaging and OneSignal need an API key?

Firebase Cloud Messaging uses an OAuth sign-in. OneSignal takes an API key or an OAuth sign-in.

### Can an agent call Firebase Cloud Messaging and OneSignal without installing anything?

Yes. Firebase Cloud Messaging has a hosted endpoint at https://fcm.googleapis.com and OneSignal at https://api.onesignal.com.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-onesignal.json, and with the fewest tokens: https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-onesignal.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "firebase-cloud-messaging", "b": "onesignal"}`. From a terminal: `anchor compare firebase-cloud-messaging onesignal`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/firebase-cloud-messaging.json and https://www.anchorterminal.com/api/v1/tools/onesignal.json

## Other comparisons with Firebase Cloud Messaging or OneSignal

- [Amazon SNS vs Firebase Cloud Messaging](https://www.anchorterminal.com/compare/amazon-sns-vs-firebase-cloud-messaging.md)
- [Amazon SNS vs OneSignal](https://www.anchorterminal.com/compare/amazon-sns-vs-onesignal.md)
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- [Courier vs OneSignal](https://www.anchorterminal.com/compare/courier-vs-onesignal.md)
- [Firebase Cloud Messaging vs Knock](https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-knock.md)
- [Firebase Cloud Messaging vs MagicBell](https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-magicbell.md)
- [Firebase Cloud Messaging vs Novu](https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-novu.md)
- [Firebase Cloud Messaging vs ntfy](https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-ntfy.md)
- [Firebase Cloud Messaging vs Pushover](https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-pushover.md)
- [Firebase Cloud Messaging vs SuprSend](https://www.anchorterminal.com/compare/firebase-cloud-messaging-vs-suprsend.md)
- [Knock vs OneSignal](https://www.anchorterminal.com/compare/knock-vs-onesignal.md)
- [MagicBell vs OneSignal](https://www.anchorterminal.com/compare/magicbell-vs-onesignal.md)
- [Novu vs OneSignal](https://www.anchorterminal.com/compare/novu-vs-onesignal.md)
- [ntfy vs OneSignal](https://www.anchorterminal.com/compare/ntfy-vs-onesignal.md)
- [OneSignal vs Pushover](https://www.anchorterminal.com/compare/onesignal-vs-pushover.md)
- [OneSignal vs SuprSend](https://www.anchorterminal.com/compare/onesignal-vs-suprsend.md)