Rclone and Syncthing are both open-source, cross-platform software tools that allow you to copy and synchronize files and directories across different devices but that is about all they have in common. They are very different tools used for different things. It is not really fair to compare them in some ways but I often hear about people wanting to use Rclone for tasks that Syncthing would be best used for and vice-versa.
- Command-line tool with a web based GUI optional.
- Can synchronize files and directories to and from a variety of cloud storage services.
- Also supports local and remote file transfers, including SFTP and FTP.
- Performs operations such as copy, move and sync.
- Allows you to manage the cloud service (i.e creating folders, deleting files, etc.)
- Syncthing core application is a command-line program with a Web based GUI.
- A continuous peer to peer file synchronization program.
- Can synchronize files and directories across different devices on a local network or over the internet.
- Does not support cloud storage services.
- Designed to be secure and private by encrypting all data.
- Provides more granular control over the synchronization process.
When to use Rclone vs. Syncthing?
If you are wanting a constant update and syncing of files between two or more computers/devices you own, Syncthing is most likely the better option. Syncthing will provide you with a continuous sync that is better than running either Rclone or Rsync over SSH on a regular cron job. The exception might be if you are syncing only occasionally, say once or twice a day. The having Syncthing running continuously is probably more than you want or need. For example if you are looking at using Syncthing to continually sync web server log files to you desktop computer to analyze Syncthing is probably not the best tool and Rclone or Rsync will be enough. If you want to sync image uploads between multiple computers and your desktop Syncthing once setup will run continuously and keep your image uploads folder in sync across as many machines as you need.
Rclone, is the perfect tool if you want to connect to a specific cloud storage service. In fact with Rclone you could easily setup a regular backup of your desktop or server files to an offsite storage service such as AWS S3 or one of their many alternatives. For example in my day to day work we run Syncthing over multiple web servers and one in office computer. All uploaded images are synced using Syncthing to each other and the in office computer. The in office computer then regularly using Rclone to copy all images from the Syncthing folder up to our Backblaze B2 bucket as a backup.
Both Rclone and Syncthing are powerful tools that can help you keep your files in sync across cloud storage services and multiple devices. The choice between the two will depend on your specific needs. Personally I use both tools, the hard part is knowing which one to use when.