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Databases · head to head

CosmosDB vs Supabase

CosmosDB logo

CosmosDB

Databases

Globally distributed, multi-model database service from Azure

From
Free
Rated
-
Full reviewWebsite
Supabase logo

Supabase

Technology

The open source Firebase alternative

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: CosmosDB autoscale provisioned throughput enforces a minimum of 1,000 RU/s, billed hourly whether or not the database is used; Supabase free tier projects auto-pause after 1 week of inactivity
  • They diverge on capability: CosmosDB covers Global Distribution, Supabase covers PostgreSQL database.
  • Prices and features above were last checked on 30 August 2026.

Where they differ

Only the attributes on which CosmosDB and Supabase actually diverge.

Attributes where CosmosDB and Supabase differ
AttributeCosmosDBSupabase
Pricing modelusage-basedUnknown
PlatformsWeb, AzureWeb, iOS, Android
CategoryDatabasesTechnology
Founded19752020

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in CosmosDB

  • Global Distribution
  • Multi-model APIs
  • Elastic Scaling
  • Five Consistency Levels
  • SLA-backed Latency
  • Automatic Indexing
  • Serverless
  • Azure Functions

Only in Supabase

  • PostgreSQL database
  • Auto-generated APIs
  • Authentication & authorization
  • Real-time subscriptions
  • Storage
  • Edge functions
  • Vector embeddings
  • Database migrations

What people use each for

The jobs each tool is most often brought in to do.

CosmosDB

  • Running a globally distributed multi model database on Azurenot Supabase
  • Serving low latency reads and writes from multiple Azure regionsnot Supabase
  • Storing document, key value and graph data behind a managed servicenot Supabase

Supabase

  • Web application backends using Postgres plus auto-generated REST/GraphQL APIsnot CosmosDB
  • Mobile app backends via Flutter/Swift/Kotlin client librariesnot CosmosDB
  • AI applications using vector/embeddings storagenot CosmosDB
  • Authentication with 20+ social providers plus email/passwordnot CosmosDB
  • File and media storage (S3-compatible with CDN) and realtime sync over WebSocketsnot CosmosDB

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

CosmosDB

  • Autoscale provisioned throughput enforces a minimum of 1,000 RU/s, billed hourly whether or not the database is used
  • Provisioned throughput is charged in every region the account is replicated to, so multi region accounts multiply the RU bill
  • Storage charges cover data, indexes and backups in each replicated region
  • Egress out of Azure and between regions is charged, though ingress is free
  • The free allowance is one account per Azure subscription, limited to 1,000 RU/s and 25 GB
  • RU/s rates vary by region and are only shown through the pricing calculator rather than a flat published rate

Supabase

  • Free tier projects auto-pause after 1 week of inactivity
  • Free tier hard caps: 500 MB database, 1 GB file storage, 5 GB egress/month, 50,000 monthly active users, max 2 active free projects per organization
  • Pro plan charges usage overages beyond included quotas, e.g. $0.00325 per MAU above 100,000 and $0.125/GB disk above 8 GB
  • SOC2/ISO 27001 certification and HIPAA (add-on) compliance require the $599/month Team plan; not available on the $25/month Pro plan

Pricing, plan by plan

CosmosDB

Free
  • Free TierFree
    • 1000 RU/s
    • 25GB storage
    • First 12 months
  • ServerlessFree
    • Pay per request
    • Auto-scaling
    • Event-driven workloads

Supabase

Free
  • FreeFree
    • 50,000 MAU
    • 500MB database
    • 5GB egress
  • Pro$25/month
    • 100,000 MAU
    • 8GB disk
    • 250GB egress
  • Team$599/month
    • SOC2 and ISO 27001
    • HIPAA add-on
    • 28-day log / 14-day backup retention
  • Enterprise$undefined/month
    • Custom limits
    • Dedicated support manager
    • 24/7/365 support

Which should you pick?

Choose CosmosDB if

  • You need global distribution.
  • You want to start without paying.
  • You work on Web, Azure.
  • You also want multi-model apis.
CosmosDB review

Choose Supabase if

  • You need postgresql database.
  • You want to start without paying.
  • You work on Web, iOS, Android.
  • You also want auto-generated apis.
Supabase review

Questions people ask

Is CosmosDB or Supabase better?
Neither clearly leads. CosmosDB starts at Free and Supabase at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, CosmosDB or Supabase?
CosmosDB starts at Free and Supabase at Free.
Does CosmosDB or Supabase run on more platforms?
CosmosDB runs on Web, Azure. Supabase runs on Web, iOS, Android.
Can I use CosmosDB for free?
Both have a free tier, so you can try either at no cost before committing.
What is CosmosDB best used for?
CosmosDB is most often used for running a globally distributed multi model database on azure, serving low latency reads and writes from multiple azure regions, storing document, key value and graph data behind a managed service. Of those, running a globally distributed multi model database on azure and serving low latency reads and writes from multiple azure regions are not what Supabase is typically brought in for.
What can CosmosDB do that Supabase cannot?
CosmosDB covers Global Distribution, Multi-model APIs, Elastic Scaling, Five Consistency Levels. Supabase covers PostgreSQL database, Auto-generated APIs, Authentication & authorization, Real-time subscriptions.

Answered from the vendors’ own pages

CosmosDB: Is there a free tier for Azure Cosmos DB?

Yes, Cosmos DB offers a free tier with 1,000 RU/s of throughput and 25 GB of storage per month for the lifetime of the account, available to new accounts.

Source
Supabase: How much does Supabase cost?

Supabase offers a free tier and three paid plans. Pro starts at $25 per month, Team at $599 per month, and Enterprise requires a custom quote. All pricing is in USD charged monthly.

Source
CosmosDB: How is Cosmos DB priced after the free tier?

Cosmos DB uses three billing models: provisioned throughput billed per request unit per second, vCore pricing for certain APIs, or serverless consumption pricing where you pay only for requests processed. Reserved capacity offers 20% discount for one year or 30% for three years.

Source
Supabase: What are Supabase's usage overage fees?

Pro plan users pay $0.00325 per monthly active user over the 100,000 included, and $0.125 per GB for database storage exceeding 8 GB per project. Compute instances cost $10 to $3,730+ per month.

Source
CosmosDB: Can I change my pricing model after choosing one?

No. Once you select a compute pricing model and API, they cannot be changed. This choice is permanent for that database.

Source
CosmosDB: Is there a trial period for Cosmos DB beyond the free tier?

Azure offers a 30-day free trial account for all Azure services. Additionally, Azure AI customers may be eligible for a 90-day free Cosmos DB subscription through the Azure AI Advantage program.

Source
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