The Access-Control-Allow-Headers response header is used in response to a preflight request which includes the Access-Control-Request-Headers to indicate which HTTP headers can be used during the actual request. This header is required if the request has an Access-Control-Request-Headers header
| Websites using header Access-Control-Allow-Headers | 553,405 |
| Percentage of websites that use Access-Control-Allow-Headers header | 0.91% |
| Total discovered header values | More than 10,000 |
| Header uses directives | Yes |
| Header values are unique or random | No |
| Most popular in the country |  United States |
| Directive | Share | Websites count | Unique Values |
|---|---|---|---|
| content-type | 78.32% | 433,406 | 2 |
| x-requested-with | 49.27% | 272,681 | 1 |
| authorization | 41.63% | 230,389 | 2 |
| origin | 31.68% | 175,311 | 1 |
| accept | 27.01% | 149,470 | 1 |
| cache-control | 13.11% | 72,544 | 1 |
| user-agent | 12.58% | 69,645 | 1 |
| * | 11.94% | 66,074 | 1 |
| if-modified-since | 11.22% | 62,116 | 1 |
| dnt | 10.01% | 55,415 | 1 |
| keep-alive | 7.10% | 39,276 | 1 |
| x-customheader | 3.61% | 19,955 | 1 |
| client-security-token | 1.72% | 9,531 | 1 |
| x-accept-charset | 1.43% | 7,935 | 1 |
| soapaction | 0.40% | 2,195 | 1 |
| typeform-version | 0.37% | 2,032 | 1 |
| x-typeform-key | 0.37% | 2,032 | 1 |
| access_token | less than 0.1% | 352 | 1 |
| Domain | Country | Rank | Contacts |
|---|---|---|---|
| United States | 31 | ||
| United States | 34 | ||
| United States | 51 | ||
| United States | 64 | ||
| United States | 77 | ||
| United States | 96 |
| Header value | Value prevalence |
|---|---|
| Content-Type, Authorization | 13% |
| * | 11% |
| origin, x-requested-with, content-type | 8% |
| Content-Type | 7% |
| Origin, X-Requested-With, Content-Type, Accept | 3% |
| X-Requested-With | 2% |
| accept, x-request, x-requested-with | 2% |
| Origin, X-Requested-With, Content-Type, Accept, Authorization | 2% |
| DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range | 1% |
| X-Accept-Charset,X-Accept,Content-Type | 1% |
| x-sap-service | 1% |
| Content-Type, Authorization, X-Requested-With | 1% |
| X-Requested-With,content-type | 1% |
| DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type | 1% |
| Content-Type,Accept | 1% |
| Origin,Content-Type,Accept,User-Agent,Cookie,Authorization,X-Auth-Token,X-Requested-With | 1% |
| Authorization, Content-Type | 1% |
| x-requested-with, Content-Type, origin, authorization, accept, client-security-token | 0% |
| DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Authorization | 0% |
| Content-Type, Authorization, Accept, X-Requested-With | 0% |
