# Content-Range header

> Indicates which portion of a resource is delivered in a partial response.

Source: https://apiguide.dev/headers/content-range
Direction: response
Registered: yes
Defined in: RFC 9110, Section 14.4 <https://www.rfc-editor.org/rfc/rfc9110.html#section-14.4>
Updated: 2026-10-14

## What is the Content-Range header?

The `Content-Range` response header describes where a returned chunk of data fits within the complete resource. It accompanies a `206 Partial Content` response and states the byte range being sent along with the total size of the full representation.

## API Usage & Best Practices

* **Reassembling downloads**: Clients use the range and total-length values to place each chunk correctly and to know when the whole resource has been received.
* **Signaling unsatisfiable ranges**: In a `416 Range Not Satisfiable` response, `Content-Range: bytes */146515` reports the total size so the client can retry with a valid range.

## Examples

```http
HTTP/1.1 206 Partial Content
Content-Range: bytes 0-1023/146515
Content-Length: 1024
```