Tips: Ctrl+F Quick Search
| Header | Description | Example |
|---|---|---|
| Accept | Specifies the content types that are acceptable for the client to receive | Accept: text/plain, text/html |
| Accept-Charset | Character encoding set acceptable to the browser. | Accept-Charset: iso-8859-5 |
| Accept-Encoding | Specify the web server return content compression encoding type that the browser can support. | Accept-Encoding: compress, gzip |
| Accept-Language | Browser acceptable language | Accept-Language: en,zh |
| Accept-Ranges | One or more sub range fields, which can request web page entities | Accept-Ranges: bytes |
| Authorization | Authorization certificate for HTTP authorization | Authorization: certificate of authorization |
| Cache-Control | Specify the caching mechanism that requests and responses follow | Cache-Control: no-cache |
| Connection | Indicates whether a persistent connection is required. (HTTP 1.1 makes persistent connection by default) | Connection: close |
| Cookie | When an HTTP request is sent, all cookie values saved under the request domain name will be sent to the web server together. | Cookie: $Version=1; Skin=new; |
| Content-Length | Requested content length | Content-Length: 348 |
| Content-Type | The requested MIME information corresponding to the entity | Content-Type: application/x-www-form-urlencoded |
| Date | Date and time when the request was sent | Date: Tue, 15 Nov 2010 08:12:31 GMT |
| Expect | Specific server behavior requested | Expect: 100-continue |
| From | Email of the user who sent the request | From: [email protected] |
| Host | Specify the domain name and port number of the requested server | Host: ach5.com |
| If-Match | Only valid if the request content matches the entity | If Match: "specific value" |
| If-Modified-Since | If the requested part is modified after the specified time, the request succeeds. If it is not modified, code 304 is returned | If-Modified-Since: Sat, 29 Oct 2010 19:43:31 GMT |
| If-None-Match | If the content has not changed, the 304 code is returned. The parameter is the Etag sent by the server previously. Compare it with the Etag responded by the server to determine whether it has changed | If-None-Match: "specific value" |
| If-Range | If the entity has not changed, the server will send the missing part of the client, otherwise the entire entity will be sent. The parameter is also Etag | If-Range: "specific value" |
| If-Unmodified-Since | The request succeeds only when the entity has not been modified after the specified time | If-Unmodified-Since: Sat, 29 Oct 2010 19:43:31 GMT |
| Max-Forwards | Limit the time that information is transmitted through agents and gateways | Max-Forwards: 10 |
| Pragma | Used to contain implementation specific instructions | Pragma: no-cache |
| Proxy-Authorization | The authorization certificate to connect to the agent | Proxy-Authorization: The authorization certificate to connect to the agent |
| Range | Request only part of the entity, specify the scope | Range: bytes=500-999 |
| Referer | The address of the previous page, followed by the current request page, that is, the origin | Referer: https://ach5.com |
| TE | The client is willing to accept the transmission code and notify the server to accept the header information | TE: trailers,deflate;q=0.5 |
| Upgrade | Specify a transport protocol to the server for conversion (if supported) | Upgrade: HTTP/2.0, SHTTP/1.3, IRC/6.9, RTA/x11 |
| User-Agent | The content of User Agent contains the information of the user who sent the request | User-Agent: Mozilla/5.0 (Linux; X11) |
| Via | Notify the intermediate gateway or proxy server address and communication protocol | Via: 1.0 fred, 1.1 nowhere.com (Apache/1.1) |
| Warning | Warning about message entities | Warn: 199 Miscellaneous warning |
| Header | Description | Example |
|---|---|---|
| Accept-Ranges | Indicates whether the server supports the specified range request and what type of segmentation request | Accept-Ranges: bytes |
| Age | Estimated time from the original server to the proxy cache formation (in seconds, non negative) | Age: 12 |
| Allow | A valid request for a network resource. If it is not allowed, 405 is returned | Allow: GET, HEAD |
| Cache-Control | Tell whether all caching mechanisms can cache and what type | Cache-Control: no-cache |
| Content-Encoding | The returned content compression encoding type supported by the web server. | Content-Encoding: gzip |
| Content-Language | Language of response body | Content-Language: en,zh |
| Content-Length | Length of response body | Content-Length: 348 |
| Content-Location | Request another alternate address for the resource | Content-Location: /index.htm |
| Content-MD5 | Return the MD5 check value of the resource | Content-MD5: MD5 check value |
| Content-Range | The byte position of this part in the whole return body | Content-Range: bytes 21010-47021/47022 |
| Content-Type | MIME type of returned content | Content-Type: text/html; charset=utf-8 |
| Date | Time when the original server message was sent | Date: Tue, 15 Nov 2010 08:12:31 GMT |
| ETag | Current value of the entity label of the request variable | ETag: “Current value of the entity label of the request variable” |
| Expires | Date and time when the response expires | Expires: Thu, 01 Dec 2010 16:00:00 GMT |
| Last-Modified | The last modification time of the requested resource | Last-Modified: Tue, 15 Nov 2010 12:45:26 GMT |
| Location | It is used to redirect the receiver to the location of non request URL to complete the request or identify new resources | Location: https://ach5.com |
| Pragma | Including the implementation of specific instructions, which can be applied to any receiver in the response chain | Pragma: no-cache |
| Proxy-Authenticate | It indicates the authentication scheme and the parameters that can be applied to the URL of the proxy | Proxy-Authenticate: Basic |
| refresh | It is used for redirection or a new resource is created and redirected 5 seconds later (proposed by Netscape and supported by most browsers) |
Refresh: 5; url= https://ach5.com
|
| Retry-After | If the entity is temporarily unavailable, notify the client to try again after the specified time | Retry-After: 120 |
| Server | Web server software name | Server: Apache/1.3.27 (Unix) (Red-Hat/Linux) |
| Set-Cookie | Set Http Cookies | Set-Cookie: UserID=JohnDoe; Max-Age=3600; Version=1 |
| Trailer | Point out that the header field exists at the end of the block transmission code | Trailer: Max-Forwards |
| Transfer-Encoding | File transmission code | Transfer-Encoding:chunked |
| Vary | Tell the downstream agent whether to use the cached response or request from the original server | Vary: * |
| Via | Tell the proxy client where the response is sent | Via: 1.0 fred, 1.1 nowhere.com (Apache/1.1) |
| Warning | Warn the entity of possible problems | Warning: 199 Miscellaneous warning |
| WWW-Authenticate | Indicates the authorization scheme that the client request entity should use | WWW-Authenticate: Basic |
HTTP request headers provide information about the request, response, or other sending entities. HTTP headers encompass four categories: general headers, request headers, response headers, and entity headers.
Each header field consists of a field name, a colon (:), and a field value.
General Headers: These can be used in both requests and responses and are associated with the message as a whole rather than with a specific resource or transaction.
Request Headers: These allow the client to pass information about itself and the desired form of the response.
Response Headers: These convey information about the server and the response itself.
Entity Headers: These define information about the transferred resource and can be used in both requests and responses.