Supabase vs Firebase: Which BaaS Actually Saves You Money in 2026?
Complete cost breakdown for 5K, 50K, and 500K users — with real pricing data
Choosing between Supabase and Firebase isn't just about features — it's about which one won't bankrupt you when you scale. Both platforms offer generous free tiers, but their pricing models diverge dramatically as your app grows.
We analyzed real-world costs for apps with 5,000 to 500,000 users. The results reveal when each platform wins — and when you're paying 3x more than you should.
TL;DR: The Bottom Line
Choose Supabase When:
- You need predictable costs — Resource-based pricing is easier to forecast
- You're building read-heavy apps — Unlimited reads vs Firebase's $0.06 per 100K
- You want SQL — PostgreSQL is more powerful than Firestore
- You value open source — Self-host option if you outgrow cloud pricing
- You're scaling past 100K users — Typically 30-50% cheaper at scale
Typical Cost: $25-200/month for most production apps
Choose Firebase When:
- You're starting small — $0 base fee vs Supabase's $25/month
- You need mobile SDKs — Best-in-class iOS/Android integration
- You want Google ecosystem — Seamless GCP, Analytics, AdMob integration
- You're write-heavy with low storage — Auth is free unlimited
- You need real-time at scale — 200K simultaneous connections on free tier
Typical Cost: $0-300/month depending on operations
Pricing Models: The Fundamental Difference
Supabase: Resource-Based Pricing
Supabase charges for what you store, not what you do:
- Database size (GB)
- Monthly Active Users (MAUs)
- File storage (GB)
- Data transfer (egress)
💡 Key Advantage: Unlimited reads and writes. Query your database 10 million times — same price as 100 queries.
Firebase: Operation-Based Pricing
Firebase charges for what you do, not what you store:
- Document reads ($0.06 per 100K)
- Document writes ($0.18 per 100K)
- Document deletes ($0.02 per 100K)
- Function invocations
⚠️ Hidden Danger: One inefficient query can read 10,000 documents and cost you $6. This happens more often than you think.
Free Tier Comparison
| Feature | Supabase Free | Firebase Spark (Free) |
|---|---|---|
| Base Cost | $0/month | $0/month |
| Database Size | 500 MB | 1 GB |
| Database Reads | Unlimited | 50,000/day |
| Database Writes | Unlimited | 20,000/day |
| Auth Users | 50,000 MAUs | Unlimited |
| File Storage | 1 GB | 5 GB |
| Bandwidth | 2 GB egress | 10 GB/month |
| Realtime | Unlimited connections | 200K simultaneous |
| Inactivity Pause | ⚠️ After 7 days | ✅ Never |
🔥 Winner for Free Tier: Firebase — No inactivity pause and unlimited auth make it better for hobby projects.
Paid Plans: Supabase Pro vs Firebase Blaze
Supabase Pro Plan ($25/month + usage)
| Resource | Included | Overage Cost |
|---|---|---|
| Database Size | 8 GB | $0.125/GB/month |
| Auth MAUs | 100,000 | $0.00325 per user |
| Storage | 100 GB | $0.021/GB/month |
| Database Egress | 50 GB | $0.09/GB |
| Storage Egress | 250 GB | $0.09/GB |
| Edge Functions | 2M invocations | $2 per 1M |
Firebase Blaze Plan ($0 base + pay-as-you-go)
| Operation | Free Tier | Cost After Free |
|---|---|---|
| Document Reads | 50K/day | $0.06 per 100K |
| Document Writes | 20K/day | $0.18 per 100K |
| Document Deletes | 20K/day | $0.02 per 100K |
| Storage | 5 GB | $0.026/GB/month |
| Bandwidth | 10 GB/month | $0.15/GB |
| Cloud Functions | 2M invocations | $0.40 per 1M |
Real-World Cost Scenarios
Scenario 1: Small SaaS (5,000 Users)
App Profile:
- 5,000 monthly active users
- 100K reads/day (3M/month)
- 10K writes/day (300K/month)
- 2 GB database
- 10 GB file storage
| Platform | Breakdown | Total/Month |
|---|---|---|
| Supabase | $25 base (all within limits) | $25 |
| Firebase |
Reads: $1.80 Writes: $5.40 Storage: $0.13 | $7.33 |
💡 Winner: Firebase — At small scale, pay-per-use beats $25 base fee.
Scenario 2: Growing App (50,000 Users)
App Profile:
- 50,000 monthly active users
- 1M reads/day (30M/month)
- 200K writes/day (6M/month)
- 10 GB database
- 80 GB file storage
| Platform | Breakdown | Total/Month |
|---|---|---|
| Supabase |
Base: $25 DB overage: $0.25 (2GB × $0.125) | $25.25 |
| Firebase |
Reads: $18 Writes: $108 Storage: $1.95 | $127.95 |
🔥 Winner: Supabase — 80% cheaper! Operation costs add up fast.
Scenario 3: High-Traffic App (200,000 Users)
App Profile:
- 200,000 monthly active users
- 5M reads/day (150M/month)
- 1M writes/day (30M/month)
- 25 GB database
- 300 GB file storage
| Platform | Breakdown | Total/Month |
|---|---|---|
| Supabase |
Base: $25 Auth: $325 (100K × $0.00325) DB: $2.13 (17GB × $0.125) Storage: $4.20 (200GB × $0.021) | $356.33 |
| Firebase |
Reads: $90 Writes: $540 Storage: $7.67 | $637.67 |
🔥 Winner: Supabase — 44% cheaper at scale.
Scenario 4: Massive Scale (500,000 Users)
App Profile:
- 500,000 monthly active users
- 10M reads/day (300M/month)
- 2M writes/day (60M/month)
- 50 GB database
- 1 TB file storage
| Platform | Breakdown | Total/Month |
|---|---|---|
| Supabase |
Base: $25 Auth: $1,300 (400K × $0.00325) DB: $5.25 (42GB × $0.125) Storage: $18.90 (900GB × $0.021) | $1,349.15 |
| Firebase |
Reads: $180 Writes: $1,080 Storage: $25.87 | $1,285.87 |
💡 Winner: Firebase — At massive scale with moderate operations, Firebase can be competitive.
Hidden Costs & Gotchas
Supabase Hidden Costs
- ❌ $25 minimum — Even if you only need $5 worth of resources
- ❌ Auth MAUs are expensive — $0.00325 per user adds up ($1,300 for 400K users)
- ❌ Egress costs — $0.09/GB can surprise you with inefficient queries
- ❌ No free backups — Point-in-time recovery requires Pro plan
- ❌ 7-day pause on free tier — Not suitable for production
Firebase Hidden Costs
- ❌ Inefficient queries are expensive — One bad query = $100+ bill
- ❌ No query cost visibility — Hard to predict bills before they arrive
- ❌ Bandwidth is pricey — $0.15/GB vs Supabase's $0.09/GB
- ❌ Realtime costs — Can explode with many concurrent connections
- ❌ Function cold starts — Slower than Supabase Edge Functions
Final Verdict: When to Choose Each
Choose Supabase If:
- ✅ You have 50K+ users and growing
- ✅ Your app is read-heavy (dashboards, analytics, content apps)
- ✅ You want predictable costs you can forecast
- ✅ You need SQL and complex queries
- ✅ You value open source and self-hosting options
Sweet Spot: 50K-500K users, read-heavy workloads
Choose Firebase If:
- ✅ You're just starting (under 10K users)
- ✅ You need best-in-class mobile SDKs
- ✅ You want $0 base cost to validate your idea
- ✅ You're building real-time collaborative apps
- ✅ You're already deep in Google ecosystem
Sweet Spot: 0-50K users, mobile-first apps
The Cost Crossover Point
For most apps, Supabase becomes cheaper than Firebase at around 30,000-50,000 monthly active users.
Below that threshold, Firebase's $0 base fee and pay-per-use model is more economical. Above it, Supabase's unlimited operations and resource-based pricing wins.