Partial Content

Overview

206 Partial Content means the server delivered only part of the resource (a byte range) that the client asked for with a Range header. The Content-Range header states which range was sent and out of what total size.

This code powers resumable downloads and media streaming, letting clients fetch just the bytes they need instead of re-downloading a whole large file.

When it happens

• When a video player requests only the byte range around the position a user seeked to, the server returns that slice as 206.
• It occurs when a download manager or curl -C - resumes a broken file by fetching just the remaining bytes.

Request / Response example

GET /video.mp4 HTTP/1.1
Host: media.example.com
Range: bytes=1048576-2097151

HTTP/1.1 206 Partial Content
Content-Range: bytes 1048576-2097151/5242880
Content-Length: 1048576
Content-Type: video/mp4
Accept-Ranges: bytes

(binary chunk)

In code

# request bytes 500-999 of a file
curl -H 'Range: bytes=500-999' https://media.example.com/video.mp4 -o part
# or resume a broken download
curl -C - -O https://media.example.com/video.mp4

const res = await fetch('/video.mp4', {
  headers: { Range: 'bytes=0-1023' }
});
console.log(res.status);            // 206
console.log(res.headers.get('Content-Range'));

Notes

• To support range requests the server should advertise Accept-Ranges: bytes and include an accurate Content-Range in the response.
• If the requested range lies beyond the file size, the server returns 416 Range Not Satisfiable instead of 206.
• Requesting several ranges at once yields a multipart/byteranges body carrying multiple slices in one 206 response.

Related status codes

Related headers

Specification