DataStax Astra DB
DB 4.9/10Serverless Apache Cassandra database-as-a-service with built-in vector search, free via a fixed monthly credit and no credit card.
DataStax Astra DB scores 4.9/10 for free value in DB. The main constraint: Free plan grants a fixed ~$25/month credit (no card) covering roughly 80 GB storage and about 30M reads / 4.5M writes across up to 5 serverless databases, which hibernate once the monthly credit is exhausted.
Free value score
4.9 / 10Show the math
Key metrics
What you get
Built-in vector search on serverless Apache Cassandra for GenAI and RAG workloads
No credit card required; a fixed monthly credit (~$25) auto-refreshes each billing cycle
Up to 5 serverless databases with REST, GraphQL, JSON (Data API) and CQL access
Pay-nothing-for-idle serverless model — no provisioning or capacity planning
Limitations
- Fixed monthly credit
Free plan provides a fixed ~$25/month credit; all storage, reads, writes, and data transfer are metered against it and the balance refreshes each billing cycle.
- Max 5 databases
No more than five Astra DB Serverless databases on the Free plan.
- Hibernation on credit exhaustion
Databases are hibernated once the monthly credit is consumed, until the next billing cycle refreshes the credit or you upgrade.
- Inactivity hibernation + deletion
Inactive databases are automatically hibernated and then scheduled for deletion on the Free plan.
- No metrics export
Free plan cannot export metrics for Astra DB Serverless databases.
- No premium networking
Premium features such as private endpoints and multi-region databases are unavailable on the Free plan.
- ~80 GB storage
The monthly credit covers roughly 80 GB of stored data; usage beyond this consumes credit faster and hastens hibernation.
- ~30M reads / 4.5M writes
The monthly credit covers roughly 30 million read and 4.5 million write operations per month before hibernation.
Sources
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"Choose the free plan for $300/year of free credit and no credit card required."
https://vercel.com/marketplace/datastax-astra-db -
"Free tier includes up to 30 million reads, 4.5 million writes and 40GB storage every month (up to $25 credit)"
https://www.openfaas.com/blog/faas-storage-cassandra-astra/ -
"Organizations on the Free plan receive a fixed amount of credits each month. Once these credits are consumed, your Astra DB Serverless databases are hibernated until the next billing cycle refreshes the credit balance... No more than five Astra DB Serverless databases."
https://docs.datastax.com/en/astra-db-serverless/administration/subscription-plans.html -
"By default, Astra DB instances on the free tier are limited to 4K operations per second. Paying customers can have the rate limits raised"
https://stackoverflow.com/questions/72847393/stargate-api-rate-limiter