AssemblyAI vs Firebase
Best-in-class speech-to-text API — Universal models, 99 languages, low-latency streaming
vs. Google's mobile & web app development platform
Pricing tiers
AssemblyAI
Free Credits
$50 in free credits on signup. Full API access.
Free
Pay-as-you-go
Per-hour billing by model. No minimum.
$0 base (usage-based)
Enterprise
Custom contracts. SLA, private deployments, BAA.
Custom
Firebase
Spark (No-cost)
Free tier with generous quotas. No credit card required. Cannot exceed free quotas.
Free
Blaze (Pay as you go)
Usage-based billing. Includes Spark quotas free, then pay Google Cloud rates. Required for Cloud Functions outbound networking, scheduled jobs, some extensions.
Custom
Free-tier quotas head-to-head
Comparing free-trial on AssemblyAI vs spark on Firebase.
| Metric | AssemblyAI | Firebase |
|---|---|---|
| auth mau | — | 50000 users/month |
| firestore deletes per day | — | 20000 docs/day |
| firestore egress gib month | — | 10 GiB/month |
| firestore reads per day | — | 50000 docs/day |
| firestore storage gib | — | 1 GiB |
| firestore writes per day | — | 20000 docs/day |
| functions cpu seconds | — | 200000 CPU-sec/month |
| functions gb seconds | — | 400000 GB-sec/month |
| functions invocations | — | 2000000 invocations/mo |
| functions outbound gb | — | 5 GB/month |
| hosting storage gb | — | 10 GB |
| hosting transfer gb month | — | 10.8 GB/month |
| phone sms verifications day | — | 10 sms/day |
| rtdb connections | — | 100 connections |
| rtdb downloaded gb month | — | 10 GB/month |
| rtdb stored gb | — | 1 GB |
| storage downloaded gb day | — | 1 GB/day |
| storage gb | — | 5 GB |
| storage operations day | — | 50000 ops/day |
Features
AssemblyAI · 11 features
- Advanced Prompting — Streaming with disfluency + code-switching + realtime diarization.
- Audio Intelligence — Sentiment, topic detection, summarization, entity detection, content safety, IAB…
- Auto Punctuation — Smart capitalization + punctuation.
- Keyterm Prompting — Boost accuracy for domain vocabulary.
- LeMUR (LLM framework) — Run LLMs over transcripts: Q&A, summary, action items.
- Medical Mode — Specialized for clinical + medical vocabulary.
- PII Redaction — Auto-redact credit cards, SSNs, addresses, emails.
- Pre-recorded Transcription — Upload audio/video URL or file → transcript.
- Realtime Streaming — WebSocket-based low-latency STT.
- Speaker Diarization — Identify who spoke when.
- Webhooks — Auto-notify when transcription finishes.
Firebase · 20 features
- A/B Testing — Experiments on Remote Config params, FCM notifications, and Analytics events. Ba…
- App Check — Attestation service: only requests from authentic, untampered app instances reac…
- App Hosting — Managed hosting for modern web apps (Next.js, Angular, SvelteKit). Git-based dep…
- Cloud Firestore — Serverless NoSQL document database. Real-time sync, ACID transactions, offline p…
- Cloud Functions — Serverless functions (Node.js/Python). Trigger on HTTP, Firestore, RTDB, Auth, S…
- Cloud Storage — Object storage for user files. Built on GCS. Security rules + signed URLs. Resum…
- Crashlytics — Real-time crash reporting for iOS/Android/Unity/Flutter. Stack traces, breadcrum…
- Data Connect — GraphQL API backed by Cloud SQL for PostgreSQL. Type-safe SDK generation. Previe…
- Dynamic Links — Deep links that survive app install. NOTE: deprecated, shutdown Aug 2025 — migra…
- FCM Topics — Publish/subscribe messaging: devices subscribe to topic names; backend sends one…
- Firebase AI Logic — Client-side SDK to call Gemini models directly from mobile/web. Formerly "Vertex…
- Firebase Authentication — Drop-in auth: email/password, phone, anonymous, 10+ federated providers, custom …
- Firebase Cloud Messaging — Push notifications for iOS, Android, Web (APNs/FCM transports). Topics, device g…
- Firebase Extensions — Pre-packaged Cloud Functions + config: Stripe, Algolia search, image resize, tra…
- Firebase Hosting — Static + dynamic hosting with global CDN. Preview channels, atomic deploys, rewr…
- Genkit — Open-source AI app framework. Unified API for Gemini, OpenAI, Ollama; tools, RAG…
- Google Analytics for Firebase — Free unlimited event tracking with audience building. BigQuery export on Blaze. …
- Performance Monitoring — App startup, HTTP network, and custom traces. Integrates with Google Analytics e…
- Realtime Database — Low-latency JSON tree database with WebSocket sync. Best for high-frequency pres…
- Remote Config — Feature flags / parameterized config with conditional targeting (user property, …
Developer interfaces
| Kind | AssemblyAI | Firebase |
|---|---|---|
| CLI | — | Firebase CLI |
| SDK | assemblyai-go, assemblyai (Node), assemblyai (Python), assemblyai (Ruby) | Admin SDK (Go), Admin SDK (Java), Admin SDK (Node.js), Admin SDK (Python), Android SDK, Apple Platforms SDK, Flutter SDK (FlutterFire), JavaScript SDK, Unity SDK |
| REST | AssemblyAI REST API | Auth REST API, Cloud Storage REST, Firebase Management API, Firestore REST API, Realtime Database REST |
| MCP | — | Firebase MCP Server |
| OTHER | Streaming WebSocket, Webhooks | Firestore gRPC, Realtime Database WebSocket |
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