starlette-compress

starlette-compress

starlette-compress is a fast and simple middleware for compressing responses in Starlette. It supports more compression algorithms than Starlette's built-in GZipMiddleware, and has more sensible defaults.

• Python 3.9+ support
• Python 3.14 compression.zstd support
• Compatible with asyncio and trio backends
• ZStd, Brotli, and GZip compression
• Sensible default configuration
• Zero-Clause BSD — public domain dedication
• Semantic Versioning compliance

Installation

pip install starlette-compress

Basic Usage

Starlette

from starlette.applications import Starlette
from starlette.middleware import Middleware
from starlette_compress import CompressMiddleware

middleware = [
    Middleware(CompressMiddleware)
]

app = Starlette(routes=..., middleware=middleware)

FastAPI

You can use starlette-compress with FastAPI too:

from fastapi import FastAPI
from starlette_compress import CompressMiddleware

app = FastAPI()
app.add_middleware(CompressMiddleware)

Advanced Usage

Changing Minimum Response Size

Control the minimum size of the response to compress. By default, responses must be at least 500 bytes to be compressed.

# Starlette
middleware = [
    Middleware(CompressMiddleware, minimum_size=1000)
]

# FastAPI
app.add_middleware(CompressMiddleware, minimum_size=1000)

Tuning Compression Levels

Adjust the compression levels for each algorithm. Higher levels mean smaller files but slower compression. Default level is 4 for all algorithms.

# Starlette
middleware = [
    Middleware(CompressMiddleware, zstd_level=6, brotli_quality=6, gzip_level=6)
]

# FastAPI
app.add_middleware(CompressMiddleware, zstd_level=6, brotli_quality=6, gzip_level=6)

Supporting Custom Content-Types

Manage the supported content-types. Unknown response types are not compressed. Check here for the default configuration.

from starlette_compress import add_compress_type, remove_compress_type

add_compress_type("application/my-custom-type")
remove_compress_type("application/json")