Softwr

Machine Learning · head to head

Milvus vs PlanetScale

Milvus logo

Milvus

Machine Learning

Open-source vector database for scalable similarity search

From
Free
Rated
-
Full reviewWebsite
PlanetScale logo

PlanetScale

Databases

The MySQL-compatible serverless database

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Milvus vector dimensions are capped at 32,768; PlanetScale pricing varies significantly across 17+ AWS and GCP regions
  • They diverge on capability: Milvus covers Billion-scale vectors, PlanetScale covers Database Branching.

Where they differ

Only the attributes on which Milvus and PlanetScale actually diverge.

Attributes where Milvus and PlanetScale differ
AttributeMilvusPlanetScale
Pricing modelfreemiumusage-based
PlatformsLinux, Mac, Windows, WebCloud-hosted (AWS, GCP, Azure)
CategoryMachine LearningDatabases
Founded20172018

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 Milvus

  • Billion-scale vectors
  • Multiple index types
  • GPU acceleration
  • Hybrid search
  • Data partitioning
  • PyTorch
  • TensorFlow
  • Hugging Face

Only in PlanetScale

  • Database Branching
  • Non-blocking Schema Changes
  • Insights
  • Horizontal Scaling
  • Connection Pooling
  • Query Caching
  • Automatic Backups
  • Global Replication

Both cover

  • Web support

What people use each for

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

Milvus

  • Self hosting a vector database for semantic searchnot PlanetScale
  • Storing and querying embeddings for retrieval augmented generationnot PlanetScale
  • Similarity search over images, audio or text at scalenot PlanetScale

PlanetScale

  • MySQL-compatible applications requiring horizontal scalingnot Milvus
  • PostgreSQL deployments with custom cluster configurationsnot Milvus
  • Multi-region database deployments on AWS or GCPnot Milvus
  • Applications requiring transparent sharding via Vitessnot Milvus

Where each one falls short

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

Milvus

  • Vector dimensions are capped at 32,768
  • A collection is limited to 64 fields, 1,024 partitions and 16 shards
  • Only 1 index is allowed per field
  • Search returns at most 16,384 vectors as top-k, and nq is capped at 16,384
  • Input and output per RPC is capped at 64 MB for insert, search and query
  • VARCHAR values are limited to 65,535 characters
  • Data loaded into query nodes cannot exceed 90% of available memory
  • An instance supports at most 65,536 collections

PlanetScale

  • Pricing varies significantly across 17+ AWS and GCP regions
  • Additional costs for EBS storage beyond base tier, backup storage, and egress
  • Dedicated PgBouncer and replicas incur separate charges
  • Metal tier pricing increases sharply with larger configurations

Pricing, plan by plan

Milvus

Free
  • Open SourceFree
    • Full features
    • Self-hosted
    • Community support
  • Zilliz CloudFree
    • Managed service
    • Free tier available

PlanetScale

Free
  • Postgres EBS Single-Node (ARM64 PS-5)$5/month
    • 512 MiB RAM
    • Single-node configuration
    • EBS storage included
  • Postgres EBS HA (ARM64 PS-5)$15/month
    • 512 MiB RAM
    • 3-node high-availability setup
    • 1 primary + 2 replicas
  • Postgres Metal (M-10)$50/month
    • 1/8 vCPU, 1 GiB RAM
    • 3-node HA configuration
    • 10 GiB NVMe storage included
  • Vitess Non-Metal 3-Node$39/month
    • Sharding-capable database
    • x86-64 architecture
    • 3-node configuration

Which should you pick?

Choose Milvus if

  • You need billion-scale vectors.
  • You want to start without paying.
  • You work on Linux, Mac, Windows, Web.
  • You also want multiple index types.
Milvus review

Choose PlanetScale if

  • You need database branching.
  • You want to start without paying.
  • You work on Cloud-hosted (AWS, GCP, Azure).
  • You also want non-blocking schema changes.
PlanetScale review

Questions people ask

Is Milvus or PlanetScale better?
Neither clearly leads. Milvus starts at Free and PlanetScale at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Milvus or PlanetScale?
Milvus starts at Free and PlanetScale at Free.
Does Milvus or PlanetScale run on more platforms?
Milvus runs on Linux, Mac, Windows, Web. PlanetScale runs on Cloud-hosted (AWS, GCP, Azure).
Can I use Milvus for free?
Both have a free tier, so you can try either at no cost before committing.
What is Milvus best used for?
Milvus is most often used for self hosting a vector database for semantic search, storing and querying embeddings for retrieval augmented generation, similarity search over images, audio or text at scale. Of those, self hosting a vector database for semantic search and storing and querying embeddings for retrieval augmented generation are not what PlanetScale is typically brought in for.
What can Milvus do that PlanetScale cannot?
Milvus covers Billion-scale vectors, Multiple index types, GPU acceleration, Hybrid search. PlanetScale covers Database Branching, Non-blocking Schema Changes, Insights, Horizontal Scaling. Both handle Web support.

Answered from the vendors’ own pages

Milvus: How much does Milvus cost?

Milvus is open-source and free to use and modify. The self-hosted version has no licensing cost. Zilliz Cloud (the managed SaaS version) does not publish pricing on the website.

Source
PlanetScale: How much does a PlanetScale Postgres database cost per month?

PlanetScale Postgres pricing starts at $5/month for single-node ARM64 configurations with 512 MiB RAM and $15/month for the same specs in high-availability mode with 1 primary and 2 replicas. Metal tier starts at $50/month for M-10 configuration (1/8 vCPU, 1 GiB RAM). Exact pricing depends on cluster size, node architecture (ARM64 vs x86-64), storage configuration, and selected AWS/GCP region.

Source
Milvus: Is there a free or open-source version of Milvus?

Yes, Milvus is fully open-source and available for free. Milvus Lite is a lightweight option for learning and prototyping that can be installed via pip.

Source
PlanetScale: Is there a free tier for PlanetScale?

PlanetScale offers a free tier for development and testing workloads. After free tier limits are reached, usage-based pricing applies starting at $5/month for the smallest Postgres single-node configuration, with costs scaling based on cluster size, compute, storage, and additional features like dedicated PgBouncer or replicas.

Source
Milvus: Does Milvus offer a managed cloud service?

Yes, Zilliz Cloud is a fully managed Milvus cloud offering with serverless and dedicated cluster options. Pricing must be requested from the company as it is not listed on the public website.

Source
PlanetScale: What is the difference between PlanetScale ARM64 and x86-64 pricing?

ARM64 instances cost significantly less than x86-64 equivalents. For example, a Postgres EBS HA cluster with 512 MiB RAM costs $15/month on ARM64 but $39/month on x86-64. This pricing difference extends across all cluster sizes, with larger x86-64 configurations reaching up to $5,599/month compared to ARM64 alternatives.

Source
PlanetScale: What is included in a PlanetScale cluster price versus additional costs?

The advertised cluster price covers the base compute and configured storage. Additional charges apply for EBS storage beyond the base allocation, backup storage, data egress, optional dedicated PgBouncer connections, and replicas beyond the base high-availability configuration. Regional pricing varies across 17+ AWS and GCP zones.

Source
Share

Related pages

More on Milvus

More on PlanetScale

Keep looking

Other head to heads