{"id":3448,"date":"2024-06-13T10:55:56","date_gmt":"2024-06-13T04:55:56","guid":{"rendered":"https:\/\/mailbluster.com\/?post_type=helps&#038;p=3448"},"modified":"2025-07-28T12:30:26","modified_gmt":"2025-07-28T06:30:26","slug":"resolve-cors-error","status":"publish","type":"helps","link":"https:\/\/mailbluster.com\/helps\/resolve-cors-error","title":{"rendered":"Resolve CORS error while using MailBluster Developer API"},"content":{"rendered":"\n<p>Here you will learn how to resolve CORS error while using MailBluster Developer API<\/p>\n\n\n\n<p>A <strong>CORS error<\/strong> occurs when you make a request from an HTML form submission or an AJAX call. This happens because anyone can intercept the request and view the secret API key, which is why <strong>CORS restrictions<\/strong> exist.<\/p>\n\n\n\n<p>If you are getting <strong>CORS errors<\/strong>, it means you are calling the MailBluster developer API directly from your <strong>frontend<\/strong>. Instead, you need to call the MailBluster developer API from your <strong>backend<\/strong>.<\/p>\n\n\n\n<p>To resolve this, send the request from your backend using languages like PHP, Node.js, Python, Ruby, etc. You can test this with Postman or a similar API testing tool to ensure it works as expected.<\/p>\n\n\n\n<p>Calling the <strong>MailBluster developer API<\/strong> from the frontend will not work due to <strong>CORS errors<\/strong> and the associated security risks. Exposing your API key publicly can lead to major security issues.<\/p>\n\n\n\n<p>Always make API calls from your backend to keep your API key secure. This approach will prevent <strong>CORS errors<\/strong> and protect your API key from being exposed.<\/p>\n","protected":false},"featured_media":0,"parent":0,"template":"","help":[9],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.1 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Resolve CORS error while using MailBluster Developer API<\/title>\n<meta name=\"description\" content=\"Learn how to resolve CORS error while using MailBluster Developer API. 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