{"json_modified": "2016-10-12T06:21:07.430438", "uuid": "531eee62-d212-4cfa-ba30-967008d80b1b", "title": "Access-Control-Request-Headers", "url": "/en-US/docs/Web/HTTP/Headers/Access-Control-Request-Headers", "tags": ["Reference", "header", "CORS", "HTTP"], "translations": [], "modified": "2016-10-12T06:21:03", "label": "Access-Control-Request-Headers", "localization_tags": [], "locale": "en-US", "id": 196459, "last_edit": "2016-10-12T06:15:30", "summary": "The <strong><code>Access-Control-Request-Headers</code></strong> request header is used when issuing a preflight request to let the server know which <a href=\"/en-US/docs/Web/HTTP/Headers\">HTTP headers</a> will be used when the actual request is made.", "sections": [{"id": "Quick_Links", "title": null}, {"id": "Syntax", "title": "Syntax"}, {"id": "Directives", "title": "Directives"}, {"id": "Examples", "title": "Examples"}, {"id": "Specifications", "title": "Specifications"}, {"id": "Browser_compatibility", "title": "Browser compatibility"}, {"id": "See_also", "title": "See also"}], "slug": "Web/HTTP/Headers/Access-Control-Request-Headers", "review_tags": []}