Why need to sync files between OneDrive and Dropbox?
The requirement of sync files between Dropbox and OneDrive is very common. For example, some people use OneDrive at work, when they go home, they prefer to Dropbox for personal use. For security, they don’t want to input password of Dropbox in companies. But, they use Onedrive which is being synced by the time when backing home, sync to Dropbox directly avoid extra steps.
The traditional and slow download & re-upload way
If you have already installed OneDrive desktop client on your computer then you can just make sure it's all synced to your PC and drag it into Dropbox folder. Web edition of OneDrive is slower. You see, this solution spends you double times. So we would like to recommend you a better way as follow.
Sync OneDrive with Dropbox in MultCloud
MultCloud is an online web service that combines all your clouds in one place. Once you are in it, you are able to manage them, transfer files across clouds, sync files between clouds and so on. MultCloud supports not only OneDrive and Dropbox, but alos OneDrive for Business and Dropbox for Business. In fact, not least, MultCloud supports nearly thirty cloud services in total: the rest are Google Drive, Box, Amazon S3, Amazon Cloud Drive, SugarSync, Alfresco, hubiC, Evernote, MEGA, Egnyte, pCloud, CloudMe, Cubby, MyDrive, WEB.DE, Yandex, HiDrive, MySQL, Flickr, MediaFire, ownCloud, ADrive, BaiDu, WebDav and FTP/SFTP.
Next are step-by-step guides on how to sync files between OneDrive and Dropbox.
Step one: In order to log in MultCloud, you should register an account or select Experience without signing up.

Step two: Add OneDrive and Dropbox separately. In MultCloud, you only need to type a display name. The authorization process is in the cloud’s official site.
Step three: If you only want to sync newest files in OneDrive to Dropbox, you can try MultCloud’s transfer feature: copy & paste, drag & drop, or Cloud Transfer Services.

Step four: Complex sync task can be completed in Cloud Sync service. MultCloud designed eight sync ways: simple sync, mirror sync, move sync, cumulative sync, update sync, incremental backup sync, full backup sync and two-way sync.

Step five: Check, re-edit or re-commit mission in Task Manager.

Conclusion
MultCloud is the easiest way to sync files between OneDrive and Dropbox. It is an app based on website that you don’t need to install a client. The safety of MultCloud is very high. MultCloud is not a storage but a media. It works as middle-man, transfer and sync spend traffic, you can use MultCloud’s points system to get more traffic.