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 | 530,291 |
| Percentage of websites that use Access-Control-Allow-Headers header | 0.84% |
| 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 | 78.91% | 418,465 | 2 |
| x-requested-with | 53.55% | 283,974 | 1 |
| authorization | 37.78% | 200,366 | 2 |
| origin | 35.24% | 186,877 | 1 |
| accept | 28.79% | 152,674 | 1 |
| cache-control | 13.59% | 72,046 | 1 |
| user-agent | 12.96% | 68,741 | 1 |
| * | 12.35% | 65,469 | 1 |
| if-modified-since | 12.19% | 64,627 | 1 |
| dnt | 10.28% | 54,527 | 1 |
| keep-alive | 7.10% | 37,630 | 1 |
| x-customheader | 3.34% | 17,721 | 1 |
| client-security-token | 2.05% | 10,852 | 1 |
| x-accept-charset | 1.02% | 5,398 | 1 |
| soapaction | 0.96% | 5,099 | 1 |
| typeform-version | 0.38% | 2,031 | 1 |
| x-typeform-key | 0.38% | 2,031 | 1 |
| access_token | <0.1% | 390 | 1 |
| Domain | Country | Rank | Contacts |
|---|---|---|---|
| United States | 31 | ||
| United States | 34 | ||
| United States | 51 | ||
| United States | 64 | ||
| United States | 112 | ||
| United States | 131 |
| Header value | Value prevalence |
|---|---|
| * | 11.53% |
| origin, x-requested-with, content-type | 9.86% |
| Content-Type, Authorization | 8.62% |
| content-type | 7.98% |
| Origin, X-Requested-With, Content-Type, Accept | 4.11% |
| X-Requested-With | 2.85% |
| Origin, X-Requested-With, Content-Type, Accept, Authorization | 2.05% |
| DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range | 2.01% |
| accept, x-request, x-requested-with | 1.92% |
| x-requested-with,content-type | 1.63% |
| DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type | 1.38% |
| Content-Type,Accept | 1.26% |
| Origin,Content-Type,Accept,User-Agent,Cookie,Authorization,X-Auth-Token,X-Requested-With | 1.19% |
| x-requested-with, Content-Type, origin, authorization, accept, client-security-token | 1.13% |
| Authorization, Content-Type | 1.03% |
| Content-Type, Authorization, X-Requested-With | 1.03% |
| X-Accept-Charset,X-Accept,Content-Type | 0.88% |
| Content-Type, soapaction | 0.80% |
| Content-Type, Authorization, Accept, X-Requested-With | 0.75% |
| Origin, Authorization, Content-Type | 0.65% |
