# Accept-Encoding header

> Declares what compression algorithms the client supports for the response payload.

Source: https://apiguide.dev/headers/accept-encoding
Direction: request
Registered: yes
Defined in: RFC 9110, Section 12.5.3 <https://www.rfc-editor.org/rfc/rfc9110.html#section-12.5.3>
Updated: 2026-07-08

## What is the Accept-Encoding header?

The `Accept-Encoding` request header advertises the compression formats (such as `gzip`, `deflate`, or `br` for Brotli) that the client is capable of decoding.

## API Usage & Best Practices

* **Enable compression at the gateway**: Ensure your API gateway or web server (Nginx, Cloudflare) automatically compresses JSON payloads using the best algorithm supported by the client.
* **Significant performance gains**: Compressing JSON responses can reduce payload size by up to 70-80% for large lists.

## Examples

```http
GET /v1/leads HTTP/1.1
Host: api.apiguide.dev
Accept-Encoding: gzip, deflate, br
```