Supabase vs Firebase (2026): Postgres or NoSQL?

Use Supabase when you need SQL, want to self-host, or are building AI features. Use Firebase when you need offline sync on mobile, or you’re already deep in the Google ecosystem. For most new web apps in 2026, Supabase is the better starting point — the pricing arithmetic alone makes Firebase hard to justify once you grow past 50K users.

Who this is for

Developers choosing a backend-as-a-service for a new project. Especially if your data has relational structure, or you’re building a TypeScript stack with Prisma or Drizzle. If you’re already running Firebase in production and not hitting a wall, this isn’t a case for migration.

Versions in scope

Supabase v1.26.05 (released 2026-05-07) — Apache 2.0 license, 102,385 GitHub stars, active daily merges as of 2026-05-15
Firebase — Google Cloud proprietary platform: Firestore, Realtime Database, Cloud Functions gen2 (gen1 deprecated for new projects), Authentication, Cloud Storage

The database architecture is the whole game

Supabase gives you a dedicated Postgres instance. Firebase gives you Firestore — a NoSQL document store with no SQL support, no JOINs, and collection-scoped queries.

This isn’t a stylistic preference. It determines how you model data, what queries you can write, and what your total infrastructure looks like.

With Supabase, a multi-tenant SaaS with workspaces, projects, tasks, users, and audit logs is one database. You query it with SQL. Row-Level Security policies live in Postgres itself — the same RLS that governs your API also applies to file storage and Edge Functions. One permission model, everywhere.

With Firebase, the same app requires Firestore collections for each resource type, manual denormalization to avoid expensive multi-collection reads, and client-side join logic when you need to display related data. The 50K read/day free limit on Firestore is easy to blow in a read-heavy app before you reach meaningful scale.

If you’re coming from SQL — and most backend developers are — Postgres vs MySQL covers why Postgres specifically has become the default for new projects in 2026. Supabase builds on that foundation.

Feature comparison

Feature	Supabase	Firebase
Database	Dedicated Postgres (v15+), full SQL, ACID	Firestore (NoSQL document) or Realtime Database (NoSQL tree)
Schema	Relational, typed, foreign keys, indexes	Schemaless documents, no JOINs
Auth	Email, magic link, OTP, OAuth (20+ providers), phone, SSO/SAML, OIDC	Email, OAuth, phone, anonymous
Real-time	Broadcast, Presence, Postgres Changes	Realtime Database WebSocket sync + Firestore snapshot listeners
Serverless functions	Edge Functions on Deno 2.x — global edge network	Cloud Functions gen2 — Google Cloud regions
File storage	S3-compatible (MinIO), RLS policies apply	Google Cloud Storage
Vector / AI	pgvector built-in — similarity search, RAG	No native vector support
Self-hosting	Full Docker Compose stack — Fly.io, Railway, any VPS	None — Google Cloud only
Offline sync	None	Firestore full offline persistence
Open source	Yes (Apache 2.0)	No
Mobile SDKs	JS/TS, Dart/Flutter, Swift, Kotlin — younger ecosystem	iOS, Android, Flutter, Unity — 10+ years of polish
Google ecosystem	Independent	Analytics, Crashlytics, Remote Config, FCM, App Distribution
Compliance	SOC2 + ISO 27001 on Team tier ($599/mo); HIPAA as paid add-on	Google Cloud compliance: SOC1/2/3, ISO, HIPAA on Blaze

Pricing: the 12× gap at 100K MAU

Supabase pricing is flat-fee per tier. Firebase pricing is consumption-based. The difference compounds fast once you cross the Firebase free-tier limits.

Supabase Pro — $25/month covers a lot

The Pro plan at $25/month includes 100K MAU, 8 GB database, 250 GB bandwidth, 100 GB storage, and 2M Edge Function invocations per month. At exactly those limits, the bill is $25/month.

Firebase Blaze — per-unit costs add up fast

Firebase’s Spark free tier is generous at small scale. But Firebase Authentication charges per MAU above 50K: $0.0055 per user in the 50K–100K tier. On a 100K MAU app, authentication alone costs $275/month before you touch Firestore reads or writes.

Worked example — 100K MAU SaaS app (5 GB data, 30M Firestore reads/month, 3M writes/month, 50 GB bandwidth, 10 GB storage, 500K function invocations):

Cost item	Supabase Pro	Firebase Blaze
Base plan / auth	$25.00	Auth: $275.00
Firestore reads (28.5M billable at $0.06/100K)	—	$17.10
Firestore writes (2.4M billable at $0.18/100K)	—	$4.32
Storage (10 GB — within included limits)	$0.00	$0.13
Functions (500K — within free allowance)	$0.00	$0.00
Bandwidth (50 GB — within included limits)	$0.00	$0.00
Total	~$25/mo	~$297/mo

At 100K MAU, Firebase runs roughly 12× the cost of Supabase — driven almost entirely by per-MAU authentication fees above 50K. At 10K MAU or below, both platforms are near-zero cost and Firebase’s Spark plan has no base fee at all. The crossover matters.

Supabase free tier: the inactivity pause

Supabase free projects pause after 1 week of inactivity. For an active app this is irrelevant. For an indie hacker’s MVP with sporadic traffic, it adds cold-wake latency on the first request after a quiet period. Firebase Spark has no equivalent behavior — worth knowing if you’re evaluating the free tiers head-to-head.

Edge Functions cold starts: Supabase averages 42ms

Supabase Edge Functions run on Deno 2.x across a global edge network. Firebase Cloud Functions gen2 run on Node.js in specific Google Cloud regions.

Supabase’s own 2025 benchmark measured Edge Function cold start performance after their runtime improvements:

Average: 42ms
P95: 86ms
P99: 460ms

Google does not publish official cold start latency figures for Firebase Cloud Functions gen2. Firebase’s documentation acknowledges that “cold starts can take significant amounts of time to complete” and recommends configuring minimum instances for latency-sensitive functions. For webhook endpoints, real-time APIs, and edge-rendered responses, Supabase Edge Functions have a documented sub-100ms P95 profile. Supabase Edge Functions run on Deno 2.x, which resolved most of the historical npm compatibility issues while keeping TypeScript-first DX.

Connection scale and Realtime limits

Supabase’s connection pooler Supavisor has handled 1,003,200 simultaneous connections across two 64-core instances in load testing, with median query duration under 2ms at 5,000 QPS. That benchmark is not the typical use case, but it illustrates there’s no hidden ceiling.

Firebase Realtime Database caps out at 200,000 simultaneous connections per instance on Blaze, with a maximum of 1,000 write operations per second per database. Horizontal scaling requires manual sharding across database instances — and Firestore queries cannot span instances.

pgvector vs. external vector databases

Supabase ships pgvector natively. If you’re building a RAG pipeline, document search, or any embedding-based feature, your vector index lives in the same Postgres database as your relational data. One query can join structured data with vector similarity results.

Firebase has no vector capability. You’d wire in Pinecone, Weaviate, or Qdrant as a separate service, manage cross-service auth, pay two bills, and build the plumbing to sync document updates across both stores.

In Supabase’s own benchmark, pgvector on a Supabase 2XL instance achieved 1,185% more queries per second than a comparable Pinecone plan at 0.98 recall — at lower cost. The gap isn’t marginal.

When to choose Supabase

SaaS apps with relational data. Users, workspaces, projects, roles, audit logs — anything with foreign keys and joins. Postgres + RLS handles multi-tenant isolation in SQL without client-side workarounds.

AI features and semantic search. pgvector is built in. One database handles relational data, full-text search, and vector similarity. No external service to provision or sync.

Latency-sensitive serverless functions. Supabase Edge Functions average 42ms cold start (P95: 86ms). Firebase Cloud Functions gen2 runs regional Node.js containers with no published latency SLA — Firebase’s own docs acknowledge cold starts “can take significant amounts of time.”

Self-hosted or data-residency requirements. The full Docker Compose stack runs on Fly.io, Railway, Hetzner, or on-prem. Apache 2.0 means no license lock-in — migrate to self-hosted without rewriting the app. Firebase locks you to Google Cloud with no exit.

TypeScript-first stacks. Supabase has first-class integrations with Next.js and Astro, including typed client libraries and Auth helpers. The Prisma or Drizzle question is orthogonal — both ORMs work with Supabase’s Postgres.

When to choose Firebase

Real-time multiplayer or offline-first mobile apps. Firebase Realtime Database’s native offline persistence, WebSocket sync, and conflict resolution handle the hard parts of mobile offline mode. Supabase has no native equivalent — building it yourself is non-trivial.

Existing Google mobile ecosystem. If your app already uses Firebase Analytics, Crashlytics, Remote Config, and FCM push notifications, adding Firestore costs zero SDK overhead. Splitting data to Supabase while keeping Firebase for analytics means two SDKs for one app. That’s only worth it if your data architecture is the actual bottleneck.

Quick public MVP with sporadic traffic. Firebase Spark has no base fee and no project pause. Supabase’s free tier pauses inactive projects. If you’re shipping a demo or a low-traffic side project and expect gaps between visits, Firebase’s always-on free tier is simpler.

Verdict

Pick Supabase if:

Your data is relational, or will become relational as the product evolves.
You’re building AI features and want vector search co-located with your data.
You’re approaching or beyond 50K MAU — the pricing arithmetic is unambiguous above that threshold.
You want a self-hosting exit ramp or need to satisfy data-residency requirements.
You’re on a TypeScript stack and want typed Postgres with RLS.

Pick Firebase if:

You need offline-first sync on mobile — this is Firebase’s clearest and least-replicable advantage.
You’re already deep in the Google mobile ecosystem and don’t want to maintain two SDKs.
You’re shipping a low-traffic public MVP and want zero friction on the free tier.

For new backend projects in 2026, Supabase is the default recommendation. Firebase wins specific workloads — mobile offline and Google ecosystem lock-in — not general backend use.

Caveats

Pricing can change. Firebase pricing in particular shifts without public notice. The worked example uses rates verified 2026-05-16. Run your own numbers at firebase.google.com/pricing before committing.
Cold start benchmarks are from Supabase’s own testing. The 42ms average, 86ms P95, and 460ms P99 figures are from Supabase’s 2025 internal benchmark (Reference 13). Google does not publish official cold start numbers for Cloud Functions gen2. Function size, runtime, and region all affect these numbers.
Firebase Firestore latency is unverifiable. Google does not publish SLA latency figures for Firestore. We did not speculate on specific ms values.
No affiliate links. Supabase has no public affiliate program as of 2026-05-16 (partner form at supabase.com/partners exists but no commission rate is published). Firebase is Google-owned with no affiliate payout. This article has no financial incentive on either side.