Learn how to upload any Google Drive file to your Dropbox folder using Google Apps Script. To get started, create a new Dropbox app, as explained in the previous Dropbox example, and get the access token to skip the OAuth2 workflow.
Also see: Upload Drive Files to Google Cloud Storage
function uploadGoogleFilesToDropbox(googleDriveFileId) { var parameters = { "path": "/PDF/labnol.pdf", "mode": "add", "autorename": true, "mute": false }; // Add your Dropbox Access Token var dropboxAccessToken = 'labnolorg-MZmqX'; var headers = { "Content-Type": "application/octet-stream", 'Authorization': 'Bearer ' + dropboxAccessToken, "Dropbox-API-Arg": JSON.stringify(parameters) }; var driveFile = DriveApp.getFileById(googleDriveFileId); var options = { "method": "POST", "headers": headers, "payload": driveFile.getBlob().getBytes() }; var apiUrl = "https://content.dropboxapi.com/2/files/upload"; var response = JSON.parse(UrlFetchApp.fetch(apiUrl, options).getContentText()); Logger.log("File uploaded successfully to Dropbox"); }