> ## Documentation Index
> Fetch the complete documentation index at: https://docs.apinizer.com/llms.txt
> Use this file to discover all available pages before exploring further.
# HTTP Request Header Values
> You can make request header values ready and selectable in API Gateways and Test Console by defining request header values globally. You can manage header values that can be used in HTTP requests and add custom header values.
Request header is an HTTP header (Http Header) that can be used in HTTP requests to provide information about the request context so that the server can adapt the response. For example, Accept- \* headers indicate the allowed and preferred formats of the response. Other headers can be used to provide authentication information (Authorization, to control caching, or to get information about user agent or referrer, etc.).
There are 33 Request Header Values by default in the Apinizer Platform:
* application/base64
* application/octet-stream
* application/pdf
* application/plain
* application/postscript
* application/powerpoint
* application/rtf
* application/x-zip-compressed
* application/xml
* application/zip
* audio/basic
* application/ecmascript
* audio/midi
* audio/mpeg
* audio/mpeg3
* audio/wav
* image/bmp
* image/gif
* image/jpeg
* image/png
* image/tiff
* multipart/x-gzip
* application/excel
* multipart/x-zip
* text/css
* text/ecmascript
* text/html
* text/javascript
* text/plain
* text/xml
* video/avi
* video/mpeg
* video/msvideo
* application/java
* video/quicktime
* application/javascript
* application/json
* application/mime
* application/mspowerpoint
* application/msword
You cannot edit and delete those added by Apinizer by default.
In addition to the above, you can add your own **Request Header Values**.
## Creating a New Request Header Value
Click the **+New** button from the **Management → System Settings → Predefined Values → Request Header Values** screen.
**An image containing Request Header Value creation settings is shown below:**
The fields used for Request Header Value creation configuration are shown in the table below.
| Field | Description |
| ----------------------------- | ---------------------------------------- |
| Header Value *(Header Value)* | Field where the header value is entered. |