> ## Documentation Index
> Fetch the complete documentation index at: https://docs.trychroma.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Chroma Configuration

> Environment variables when self-hosting a Chroma server.

Self-hosted Chroma servers have configurations that can be used to change
telemetry destinations, host and port, and other behaviors.

Chroma can be configured through YAML and environment variables.

## Current Operator-Facing Env Vars

These are the main environment variables for a current self-hosted Chroma server.

| Env var                           | What it controls                        | Default or notes                                                                           |
| --------------------------------- | --------------------------------------- | ------------------------------------------------------------------------------------------ |
| `CHROMA_PERSIST_PATH`             | Directory used for persisted data       | Default: `./chroma` in the frontend config. Container deployments typically mount `/data`. |
| `CHROMA_ALLOW_RESET`              | Enables destructive reset operations    | Default: `false`.                                                                          |
| `CHROMA_PORT`                     | HTTP port for the frontend server       | Default: `8000`.                                                                           |
| `CHROMA_LISTEN_ADDRESS`           | Bind address for the frontend server    | Default: `0.0.0.0`.                                                                        |
| `CHROMA_MAX_PAYLOAD_SIZE_BYTES`   | Maximum request payload size            | Default: `41943040` (40 MiB).                                                              |
| `CHROMA_CORS_ALLOW_ORIGINS`       | Allowed CORS origins                    | Current config key accepts a list, for example `["*"]`.                                    |
| `CHROMA_SQLITEDB__MIGRATION_MODE` | SQLite migration mode                   | Allowed values: `apply`, `validate`. Default: `apply`.                                     |
| `CHROMA_SQLITEDB__HASH_TYPE`      | SQLite migration hash algorithm         | Allowed values: `md5`, `sha256`. Default: `md5`.                                           |
| `CHROMA_SQLITE_FILENAME`          | SQLite file name under the persist path | Default: `chroma.sqlite3`.                                                                 |

These are specifically for OpenTelemetry:

| Env var                               | What it controls            | Default or notes                                    |
| ------------------------------------- | --------------------------- | --------------------------------------------------- |
| `CHROMA_OPEN_TELEMETRY__ENDPOINT`     | OpenTelemetry OTLP endpoint | Used for traces in current deploy docs.             |
| `CHROMA_OPEN_TELEMETRY__SERVICE_NAME` | OpenTelemetry service name  | Default: `chromadb`.                                |
| `OTEL_EXPORTER_OTLP_HEADERS`          | OTLP exporter headers       | Commonly used for auth headers when sending traces. |

## Legacy Auth Settings

Built-in auth changed significantly before the Rust rewrite, and Chroma `v1.0.0` no
longer ships built-in authentication implementations. You may still see these variables
in older examples and migration notes:

* `CHROMA_SERVER_AUTHN_PROVIDER`
* `CHROMA_SERVER_AUTHN_CREDENTIALS`
* `CHROMA_SERVER_AUTHN_CREDENTIALS_FILE`
* `CHROMA_SERVER_AUTHZ_PROVIDER`
* `CHROMA_SERVER_AUTHZ_CONFIG`
* `CHROMA_SERVER_AUTHZ_CONFIG_FILE`
* `CHROMA_AUTH_TOKEN_TRANSPORT_HEADER`

Treat these as historical unless you are intentionally working with older Python-era
server configurations.