Update README.md

README.md

@@ -260,6 +260,7 @@ API | Description | Auth | HTTPS | CORS |
 | [GitHub](https://docs.github.com/en/free-pro-team@latest/rest) | Make use of GitHub repositories, code and user info programmatically | `OAuth` | Yes | Yes |
 | [Gitlab](https://docs.gitlab.com/ee/api/) | Automate GitLab interaction programmatically | `OAuth` | Yes | Unknown |
 | [Gitter](https://developer.gitter.im/docs/welcome) | Chat for Developers | `OAuth` | Yes | Unknown |
+| [Hexabin](http://hexabin-api.com/) | Convert and retrieve hexadecimal, binary, decimal, and octal values with ease | No | No | Unknown |
 | [HTTP2.Pro](https://http2.pro/doc/api) | Test endpoints for client and server HTTP/2 protocol support | No | Yes | Unknown |
 | [IBM Text to Speech](https://cloud.ibm.com/docs/text-to-speech/getting-started.html) | Convert text to speech | `apiKey` | Yes | Yes |
 | [IBM Visual Recognition](https://cloud.ibm.com/apidocs/visual-recognition/visual-recognition-v3) | Visual Recognition with pretrained or user trained model | `apiKey` | Yes | Unknown |