Accept-Ranges

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The HTTP Accept-Ranges response header is used by the server to advertise its support for range requests, allowing clients to request part or several parts of a resource. The value of this header indicates the unit that can be used to define a range.

For example, a response with an Accept-Ranges header indicates that the server is capable of resuming an interrupted download instead of a client restarting the transfer in full.

Header type	Response header
Forbidden header name	No

Syntax

http

Accept-Ranges: <range-unit>
Accept-Ranges: none

Directives

<range-unit>: The range unit that the server supports, although bytes is the only range unit formally defined by RFC 7233. Range units are registered in the HTTP Range Unit Registry.
none: No range unit is supported. This is equivalent to omitting the header and is, therefore, rarely used. This value was used in legacy browsers to disable or remove the pause buttons in the download manager if servers had no support for range requests.

Examples

http

Accept-Ranges: bytes

Specifications

Specification
HTTP Semantics # field.accept-ranges

Browser compatibility

BCD tables only load in the browser