Azure Cosmos DB vs FaunaDB: Which is Better in 2026?
Choosing between Azure Cosmos DB and FaunaDB comes down to understanding what each tool does best. This comparison breaks down the key differences so you can make an informed decision based on your specific needs, not marketing claims.
Bottom line: Azure Cosmos DB wins this matchup. PostgreSQL is our overall Data & Databases pick. PostgreSQL is our free Data & Databases pick. Pick FaunaDB if you need its specific feature set.
Short on time? Here's the quick answer
We've tested both tools. Here's who should pick what:
Azure Cosmos DB
Globally distributed multi-model database on Azure
Best for you if:
- • You want multi-model database
- • You want global distribution
FaunaDB
Serverless document database with GraphQL
Best for you if:
- • You want serverless database
- • You want global distribution
| At a Glance | Azure Cosmos DB | FaunaDB |
|---|---|---|
Starts at | $0.008/100 RU/s/hourProvisioned | Custom |
Best For | Data & Databases | Data & Databases |
Rating | 4.2/5 | 4.4/5 |
Free plan | No | No |
Choose Azure Cosmos DB or FaunaDB?
Choose Azure Cosmos DB if
Globally distributed multi-model database on Azure
- You want multi-model database
- You want global distribution
Choose FaunaDB if
Serverless document database with GraphQL
- You want serverless database
- You want global distribution
| Feature | Azure Cosmos DB | FaunaDB |
|---|---|---|
| Pricing Model | Paid | Paid |
| User Rating | ★4.2/5 68 reviews | ★4.4/5 93 reviews |
| Categories | Data & DatabasesCloud & Infrastructure | Data & DatabasesServerless |
In-Depth Analysis
Azure Cosmos DB
Globally distributed multi-model database on Azure
Azure Cosmos DB offers a generous Free Tier, making it accessible for initial development.
Watch out
Backup storage costs can add up
Strengths
- +Multi-model database
- +Global distribution
- +Multiple consistency levels
- +Serverless option
- +Good for geo-distributed apps
Weaknesses
- -Expensive
- -Complex pricing (RUs)
- -Vendor lock-in
- -Learning curve
- -Some limitations per model
Key features
FaunaDB
Serverless document database with GraphQL
FaunaDB's pricing is quite generous, especially with its robust Free tier offering 100K reads, 50K writes, and 500K compute ops, which is substantial for many small projects.
Watch out
Data storage costs not explicitly detailed
Strengths
- +Serverless database
- +Global distribution
- +ACID transactions
- +GraphQL support
- +Good for serverless
Weaknesses
- -Expensive at scale
- -Learning curve
- -FQL unique
- -Debugging harder
- -Vendor lock-in
Key features
Pricing: Azure Cosmos DB vs FaunaDB
| Plan | Azure Cosmos DB | FaunaDB |
|---|---|---|
| Tier 1 | Free Tier | Free |
| Tier 2 | $0.25 /1M RUs Serverless | Free Pay as you go |
| Tier 3 | $0.008 /100 RU/s/hour Provisioned | N/A |
Pricing verified from each vendor's public pricing page. Compare in detail on Azure Cosmos DB pricing and FaunaDB pricing.
Who Should Use What?
On a budget?
Both are paid. Compare plans on their websites.
Go with: Azure Cosmos DB
Want the highest-rated option?
Azure Cosmos DB: 4.2/5 (68 reviews). FaunaDB: 4.4/5 (93 reviews).
Go with: FaunaDB
Value user reviews?
Azure Cosmos DB: 68 reviews (4.2/5). FaunaDB: 93 reviews (4.4/5).
Go with: FaunaDB
3 Questions to Help You Decide
What's your budget?
Both are paid. Pricing won't help you decide here.
What's your use case?
Both are data & databases tools. Compare their specific features to decide.
How important are ratings?
FaunaDB is rated higher: 4.4/5 vs 4.2/5.
Key Takeaways
Azure Cosmos DB
- Our pick for this comparison
FaunaDB
- Higher user rating: 4.4/5 vs 4.2/5
- Larger review base (93 reviews)
The Bottom Line
Azure Cosmos DB wins this matchup. PostgreSQL is our overall Data & Databases pick. PostgreSQL is our free Data & Databases pick.
Frequently Asked Questions
Is Azure Cosmos DB or FaunaDB better?
Azure Cosmos DB is rated in our evaluation. Both are paid.
What are Azure Cosmos DB and FaunaDB used for?
Azure Cosmos DB: Globally distributed multi-model database on Azure. FaunaDB: Serverless document database with GraphQL.
What does Azure Cosmos DB cost vs FaunaDB?
Azure Cosmos DB is a paid tool. FaunaDB is a paid tool. Visit their websites for detailed pricing.