Databases · head to head
Convex vs Zilliz
Convex
Databases
Reactive backend combining a document database, TypeScript server functions and live queries, source-available under the Functional Source Licence.
- From
- Free
- Rated
- -
Zilliz
Databases
Managed vector database and vector lakebase for AI applications
- From
- Free
- Rated
- -
The short version
- Each has a real cost: Convex the Functional Source Licence is not an OSI open source licence: competing use is prohibited until each release reaches its second anniversary and converts to Apache 2.0, so you may self-host but you may not build a service on it.; Zilliz pricing structure not publicly disclosed, requires sales contact
- They diverge on capability: Convex covers Reactive queries, Zilliz covers Vector indexing.
- Prices and features above were last checked on 30 August 2026.
Where they differ
Only the attributes on which Convex and Zilliz actually diverge.
Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated), category (Databases).
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 Convex
- Reactive queries
- TypeScript server functions
- ACID transactions
- Document database
- Scheduling and workflows
- File storage
- Text and vector search
- End-to-end types
Only in Zilliz
- Vector indexing
- Distributed architecture
- SQL interface
- Tensor support
- Real-time search
- Cloud-native
- Open-source compatible
What people use each for
The jobs each tool is most often brought in to do.
Convex
- Collaborative applications where several users see the same data and every client must reflect a change immediatelynot Zilliz
- Agent backends that need durable state, scheduled work and transactional writes without assembling a queue, a database and a cachenot Zilliz
- Small product teams who need a complete backend, including auth integration, file storage and subscriptions, without hiring infrastructure engineersnot Zilliz
- Prototypes that must become production without a rewrite of the data layer, where end-to-end TypeScript types remove a class of integration bugsnot Zilliz
Zilliz
- Build retrieval-augmented generation (RAG) systemsnot Convex
- Implement semantic search over documentsnot Convex
- Create multimodal search with text and imagesnot Convex
- Power recommendation engines with vector similaritynot Convex
- Enable similarity search on user embeddingsnot Convex
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Convex
- The Functional Source Licence is not an OSI open source licence: competing use is prohibited until each release reaches its second anniversary and converts to Apache 2.0, so you may self-host but you may not build a service on it.
- Transactions are bounded at one second of user code, 16 MiB read and written, 32,000 documents scanned and 16,000 written, so every backfill, migration or bulk import has to be chunked into scheduled batches rather than written as a single operation.
- There is no SQL and no query planner; you declare up to 32 indexes per table and traverse them, and joins are loops in TypeScript, so an unanticipated access pattern requires a schema and index change rather than a new query.
- It is not an analytical database, so reporting means streaming data out to a warehouse and BI tools cannot be pointed at Convex directly, which adds a pipeline the architecture diagram did not originally include.
- The application is written against Convex's function and client APIs rather than a standard protocol, so leaving means rewriting the data access layer and replacing the reactivity model, not repointing a connection string.
Zilliz
- Pricing structure not publicly disclosed, requires sales contact
- Operational complexity for self-hosted Milvus deployments
- Learning curve for those unfamiliar with vector databases
- Limited built-in analytics compared to some alternatives
Pricing, plan by plan
Convex
Free- Free & StarterFree
- Supports 1-6 developers
- Reactive database
- File storage
- Professional$25/month per developer
- Supports up to 20 developers
- All Starter features
- Log streaming
- Business & Enterprise$2500/month minimum
- Supports 50+ developers
- SAML/SSO
- Service SLAs
Zilliz
FreeNo published plan breakdown. See the Zilliz review.
Which should you pick?
Choose Convex if
- You need reactive queries.
- You want to start without paying.
- You also want typescript server functions.
Choose Zilliz if
- You need vector indexing.
- You want to start without paying.
- You work on Cloud, Self-hosted.
- You also want distributed architecture.
Questions people ask
- Is Convex or Zilliz better?
- Neither clearly leads. Convex starts at Free and Zilliz at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Convex or Zilliz?
- Convex starts at Free and Zilliz at Free.
- Does Convex or Zilliz run on more platforms?
- Convex runs on Web. Zilliz runs on Cloud, Self-hosted.
- Can I use Convex for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Convex best used for?
- Convex is most often used for collaborative applications where several users see the same data and every client must reflect a change immediately, agent backends that need durable state, scheduled work and transactional writes without assembling a queue, a database and a cache, small product teams who need a complete backend, including auth integration, file storage and subscriptions, without hiring infrastructure engineers, prototypes that must become production without a rewrite of the data layer, where end-to-end typescript types remove a class of integration bugs. Of those, collaborative applications where several users see the same data and every client must reflect a change immediately and agent backends that need durable state, scheduled work and transactional writes without assembling a queue, a database and a cache are not what Zilliz is typically brought in for.
- What can Convex do that Zilliz cannot?
- Convex covers Reactive queries, TypeScript server functions, ACID transactions, Document database. Zilliz covers Vector indexing, Distributed architecture, SQL interface, Tensor support.
Answered from the vendors’ own pages
Convex: Is Convex open source?
It is source-available under FSL-1.1-Apache-2.0. You may read, modify and self-host it, but competing use is prohibited until each release converts to Apache 2.0 on its second anniversary.
Zilliz: What is the difference between Milvus and Zilliz Cloud?
Milvus is the open-source vector database that you can self-host. Zilliz Cloud is the fully managed service built on Milvus that removes operational overhead and handles scaling automatically.
SourceConvex: Can I self-host it?
Yes. The backend, dashboard and CLI can run on your own infrastructure, with most of the features of the cloud product. Self-hosted instances include a telemetry beacon that can be disabled.
Zilliz: How many vectors can Zilliz handle?
Milvus and Zilliz Cloud can store and search billions of vectors through their distributed architecture that separates storage and compute layers.
SourceConvex: Does it support SQL?
No. Data is accessed through a TypeScript query builder over declared indexes. Relationships are traversed in code, which is explicit and type-safe but means no ad hoc querying.
Zilliz: Is Milvus open-source?
Yes, Milvus is open-source under the Apache License 2.0 and is part of the LF AI & Data Foundation.
SourceConvex: What happens if a mutation exceeds the limits?
It fails rather than running longer, so bulk work must be split into batches and scheduled. The limits are per transaction: one second of user code, 16 MiB read and written, 32,000 documents scanned and 16,000 written.
Zilliz: What pricing does Zilliz Cloud offer?
Zilliz Cloud pricing is not publicly listed and requires contacting their team to discuss your specific scale and use case requirements.
SourceConvex: How does reactivity actually work?
Queries are deterministic functions and Convex records the data each one read. When a mutation changes that data, affected queries are re-run and subscribed clients receive the new result, so cache invalidation is handled by the platform.
Related pages
Other head to heads
- Convex vs PostgreSQL
- Convex vs Airtable
- Convex vs Cockroach Labs
- Convex vs Amazon Aurora
- Convex vs Readyset
- Convex vs FaunaDB
- Convex vs LanceDB
- Convex vs Xata
- Convex vs Materialize
- Convex vs BigQuery
- Convex vs dbt
- Convex vs Apache Doris
- Convex vs ArangoDB
- Convex vs Canary Labs
- Convex vs Chroma
- Convex vs Cloudinary
- Convex vs DynamoDB
- Convex vs Apache Solr
- Convex vs Qdrant
- Convex vs Vespa
- Convex vs Marqo
- Convex vs DataStax
- Convex vs Elasticsearch
- Convex vs Meilisearch
- Convex vs Typesense
- Convex vs OpenSearch
- Convex vs SurrealDB
- Convex vs StarRocks
- Convex vs Teradata
- Convex vs TIBCO Enterprise Message Service
- Convex vs Timeplus
- Convex vs turbopuffer
- Zilliz vs PostgreSQL
- Zilliz vs Airtable
- Zilliz vs Cockroach Labs
- Zilliz vs Amazon Aurora
- Zilliz vs Readyset
- Zilliz vs FaunaDB
- Zilliz vs LanceDB
- Zilliz vs Xata
- Zilliz vs Materialize
- Zilliz vs BigQuery
- Zilliz vs dbt
- Zilliz vs Apache Doris
- Zilliz vs ArangoDB
- Zilliz vs Canary Labs
- Zilliz vs Chroma
- Zilliz vs Cloudinary
- Zilliz vs DynamoDB
- Zilliz vs Apache Solr
- Zilliz vs Qdrant
- Zilliz vs Vespa
- Zilliz vs Marqo
- Zilliz vs DataStax
- Zilliz vs Elasticsearch
- Zilliz vs Meilisearch
- Zilliz vs Typesense
- Zilliz vs OpenSearch
- Zilliz vs SurrealDB
- Zilliz vs StarRocks
- Zilliz vs Teradata
- Zilliz vs TIBCO Enterprise Message Service
- Zilliz vs Timeplus
- Zilliz vs turbopuffer