Backend Platform Pricing: Supabase vs Firebase vs AWS Amplify

Critical Cost Reality Summary

Free Tier Operational Limits

Platform	Database	Monthly Users	Daily Operations	Storage	Critical Limitations
Supabase	500MB PostgreSQL	50,000 MAU	Unlimited reads/writes	1GB + 5GB egress	Projects pause after 1 week inactivity
Firebase	1GB Firestore	Unlimited	50k reads, 20k writes	5GB	Quotas hit within hours on real apps
AWS Amplify	25GB DynamoDB	50,000 Cognito MAU	20k Lambda requests	5GB S3 + 15GB transfer	12-month expiration cliff

Production Cost Reality (25k Active Users)

• Supabase: $40-60/month (predictable)
• Firebase: $80-200+/month (operation-dependent)
• AWS: $70-150/month (optimized) | $300+/month (typical)

Critical Failure Scenarios

Traffic Spike Financial Impact

Firebase: Most dangerous for billing surprises

• Real case: $40 → $800+ overnight from Reddit traffic
• Root cause: Unoptimized real-time listeners on entire collections
• Memory leak pattern: onSnapshot() without proper unsubscribe
• No spend caps available - only email alerts after damage

Supabase: Safest financial protection

• Spend caps actually work - service pauses instead of charging
• Set $100/month limit prevents bankruptcy scenarios
• Predictable scaling: $75 → $200 over 6 months is typical

AWS: Most complex failure modes

• Data transfer between regions kills budgets ($0.02/GB adds up)
• NAT Gateway fees: $45/month baseline
• CloudWatch logs can cost $25+/month if debug enabled
• Real costs typically 2-3x calculator estimates

Common Implementation Failures

Firebase Query Disasters:

• Missing .limit(100) pulls entire collections
• Single social media post reactions consume daily write quota
• Real-time listeners trigger on every document in collection
• Dashboard components burn through 50k reads in hours

AWS Configuration Traps:

• Lambda in us-east-1, RDS in us-west-2 = massive data transfer costs
• 267 services with independent billing dimensions
• Forgotten debug logs accumulate charges
• Cross-AZ data transfer fees not included in calculators

Technical Debt and Migration Reality

Platform Lock-in Severity

Firebase: Hardest to escape

• Firestore data export is complex and slow
• Cloud Functions use proprietary APIs
• Real-time sync features don't port to other platforms

Supabase: Most migration-friendly

• PostgreSQL standard format enables clean data export
• Auth and real-time features require rebuilding
• SQL knowledge transfers to other PostgreSQL hosts

AWS: Service-dependent complexity

• Lambda functions port reasonably well
• DynamoDB requires significant data modeling changes
• 20+ interconnected services create migration paralysis

Resource Requirements for Management

Platform	Skill Level Required	Monthly Management Hours	Key Expertise Needed
Supabase	Junior developer	2-4 hours	PostgreSQL basics, API design
Firebase	Mid-level developer	8-12 hours	Google Cloud ecosystem, Firestore optimization
AWS	Senior DevOps engineer	16+ hours	CloudFormation, IAM policies, cost optimization

Decision Framework by Team Context

Solo Developer/Indie Team

Recommendation: Supabase

• Free tier supports real applications
• Predictable scaling costs prevent runway destruction
• Single person can manage entire stack

Small Team (2-5 developers)

Recommendation: Supabase unless specific requirements

• Time better spent on features than infrastructure optimization
• No dedicated DevOps expertise required
• Avoid Firebase unless team has proven Google Cloud experience

Mid-size Team (6-20 developers)

Platform choice depends on team expertise:

• Firebase: Only if team has deep Google Cloud knowledge
• AWS: Only if someone fluent in CloudFormation and IAM debugging
• Supabase: Default safe choice for product-focused teams

Large Team (20+ developers)

AWS wins for cost optimization at scale

• Requires dedicated DevOps engineering investment
• Cost savings offset by engineering overhead
• Firebase viable for Google ecosystem teams
• Supabase for teams prioritizing development velocity

Critical Warnings and Gotchas

Firebase Hidden Costs

• SMS authentication: $0.10+ per verification in Europe
• Regional data transfer fees compound quickly
• Real-time listeners create memory leaks if not properly unsubscribed
• Operations-heavy apps face exponential cost scaling

AWS Complexity Tax

• 267 services each with independent billing models
• Mandatory supporting services not mentioned in pricing
• Enterprise discounts don't apply to all services
• Data transfer costs between availability zones accumulate

Supabase Scale Limitations

• Team plan jump to $599/month expensive for growing startups
• Point-in-time recovery backup: additional $100/month
• Project pausing on free tier requires active monitoring

Spend Limit Effectiveness

Platform	Spend Limits Work?	Protection Method	Failure Mode
Supabase	✓ Yes	Service pauses gracefully	None - actually works
Firebase	✗ No	Email alerts only	Charges continue after alert
AWS	⚠️ Complex	Budget alerts + manual shutoffs	Requires custom automation

Time-to-Market Impact

Fastest to ship: Supabase (1 week for full-stack MVP)
Medium complexity: Firebase (requires query optimization knowledge)
Highest complexity: AWS (infrastructure setup can take weeks)

Critical insight: Teams spending 3+ months on platform evaluation often run out of runway before launching. Pick Supabase for speed, optimize later when revenue justifies engineering investment.

Real-World Bill Analysis

Actual Monthly Costs (Same 2k User Todo App)

• Supabase: $0 (free tier sufficient)
• Firebase: $12/month (Firestore reads from real-time listeners)
• AWS: $23/month (DynamoDB streams + CloudWatch logs)

Viral Traffic Response (Reddit Front Page)

• Supabase: Service pauses at spend cap, resume when ready
• Firebase: $50 → $1,200+ overnight (comment system real-time listeners)
• AWS: $50 → $600+ in 2 days (data transfer costs)

Platform Selection Heuristic

Choose Supabase if: Predictable costs matter more than specific features
Choose Firebase if: Google ecosystem integration and offline sync required
Choose AWS if: Team has dedicated DevOps expertise and scale demands optimization

Default recommendation: Start with Supabase, migrate when rich enough to afford proper DevOps engineering.