Accept-Ranges header

The HTTP Accept-Ranges {{Glossary("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	{{Glossary("Response header")}}

Syntax

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

Accept-Ranges: bytes

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