Firebase vs Resend
Google's mobile & web app development platform
vs. The email API for developers — built by the Nodemailer team
Pricing tiers
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
Resend
Free
3,000 emails/month, 100 emails/day. 1 custom domain. Ideal for side projects.
Free
Pro — 50k
50,000 emails/month. 10 custom domains. Priority support.
$20/mo
Pro — 100k
100,000 emails/month. 10 custom domains.
$35/mo
Scale — 100k+
Tiered from 100k → 2.5M emails/month. Dedicated IP add-on available.
$90/mo
Scale — 2.5M
2.5M emails/month.
$1150/mo
Enterprise
3M+/month, dedicated IP included, SSO, custom contract.
Custom
Free-tier quotas head-to-head
Comparing spark on Firebase vs free on Resend.
| Metric | Firebase | Resend |
|---|---|---|
| auth mau | 50000 users/month | — |
| custom domains | — | 1 domains |
| emails per day | — | 100 emails/day |
| emails per month | — | 3000 emails/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
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, …
Resend · 12 features
- Audiences — Contact list management with custom fields.
- Batch Send — Send up to 100 emails in one API call.
- Broadcasts — Bulk email campaigns with audiences, A/B testing, analytics.
- Dedicated IP — Add-on for high-volume senders. Auto warmup.
- Domains — DKIM/SPF/DMARC auto-verification. Per-domain analytics.
- Idempotency — Prevent duplicate sends with Idempotency-Key header.
- Logs + Analytics — Full email logs, delivery heatmap, events table.
- React Email — OSS library (3M+ downloads) to compose emails in React/JSX.
- Scheduled Send — scheduledAt parameter for future delivery.
- Send API — POST /emails endpoint to send. Supports attachments, scheduled send, idempotency…
- Suppressions — Auto-managed bounce + complaint list. API to add/remove.
- Webhooks — Email lifecycle events: sent, delivered, bounced, complained, opened, clicked.
Developer interfaces
| Kind | Firebase | Resend |
|---|---|---|
| CLI | Firebase CLI | Resend CLI |
| SDK | 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 | react-email, resend-go, resend-node, resend-php, resend-python, resend-ruby |
| REST | Auth REST API, Cloud Storage REST, Firebase Management API, Firestore REST API, Realtime Database REST | Resend REST API |
| MCP | Firebase MCP Server | — |
| OTHER | Firestore gRPC, Realtime Database WebSocket | SMTP Relay, Webhooks (Svix) |
Staxly is an independent catalog of developer platforms. Outbound links to Firebase and Resend are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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