# Compression

Uncompressed vectors can be large. Compressed vectors lose some information, but they use fewer resources and can be very cost effective.

## Vector quantization

To balance resource costs and system performance, consider one of these options:

- **[Rotational Quantization (RQ)](compression-rq-compression.md)** (_recommended_)
- **[Product Quantization (PQ)](compression-pq-compression.md)**
- **[Binary Quantization (BQ)](compression-bq-compression.md)**
- **[Scalar Quantization (SQ)](compression-sq-compression.md)**

You can also [disable quantization](compression-uncompressed.md) for a collection.

:::callout{intent="info" title="Compression by Default"}
Starting with `v1.33`, you can set a default quantization for new collections using the [`DEFAULT_QUANTIZATION`](../database-configuration/overview.md#DEFAULT_QUANTIZATION) environment variable. This variable is not set by default, meaning no quantization is applied unless you explicitly configure it. When set (e.g., to 8-bit [RQ quantization](compression-rq-compression.md)), all newly created collections will use that quantization setting. Note that once set on a collection, quantization can't be disabled. Default quantization won't be applied to a collection if the index type isn't supported (for example PQ and SQ aren't supported for the flat index).
:::

## Multi-vector encoding

Aside from quantization, Weaviate also offers encodings for multi-vector embeddings:

- **[MUVERA encoding](compression-multi-vectors.md)**

## Related pages

- [Agents](./agents-index.md)
- [AI-assisted Weaviate code generation](./ai-assisted-vibe-coding-index.md)
- [APIs](./apis-index.md)
- [Authorization and authentication](./authorization-and-authentication-index.md)
- [Benchmarks](./benchmarks-index.md)
- [Best practices](./best-practices-index.md)
- [Client libraries](./clients-index.md)
- [Client Libraries / SDKs](./client-libraries-index.md)
- [Cloud](./cloud-index.md)
- [Cloud account management](./cloud-account-management-index.md)

# Agent Instructions

This portal answers questions programmatically. To receive a synthesized,
source-cited answer instead of crawling page by page, append the `?ask=`
query parameter to any page URL on this site:

    /guides/quickstart?ask=how+do+I+authenticate

Optional parameters:

- `&goal=<what-you-are-trying-to-do>` steers the answer toward your
  objective (e.g. `&goal=write+a+python+client`).
- `&version=<label>` scopes the answer to a mounted version when the
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The response is `text/markdown`: the answer followed by a `# Sources` list
of the portal pages it was grounded in. Status codes are the contract:

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For the full corpus map read `llms.txt` at the site root; for the tool
surface (search + page fetch as MCP tools) see `/mcp`.