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The Pragma
HTTP/1.0 general header is an implementation-specific header that may have various effects along the request-response chain. It is used for backwards compatibility with HTTP/1.0 caches where the Cache-Control
HTTP/1.1 header is not yet present.
Note: Pragma
is not specified for HTTP responses and is therefore not a reliable replacement for the general HTTP/1.1 Cache-Control
header, although it does behave the same as Cache-Control: no-cache
, if the Cache-Control
header field is omitted in a request. Use Pragma
only for backwards compatibility with HTTP/1.0 clients.
Header type | General header, but response behavior is not specified and thus implementation-specific. |
---|---|
Forbidden header name | no |
CORS-safelisted response-header | yes |
Syntax
Pragma: no-cache
Directives
- no-cache
-
Same as
Cache-Control: no-cache
. Forces caches to submit the request to the origin server for validation before releasing a cached copy.
Examples
Pragma: no-cache
Specifications
Specification | Title |
---|---|
RFC 7234, section 5.4: Pragma | Hypertext Transfer Protocol (HTTP/1.1): Caching |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Feature | Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | Servo |
---|---|---|---|---|---|---|---|
Basic Support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Feature | Android | Chrome for Android | Edge Mobile | Firefox for Android | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|
Basic Support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |