How to uninstall Syncthing on Mac

Syncthing keeps your device's sync identity, the certificate and private key that your other Syncthing devices trust, in ~/Library/Application Support/Syncthing next to config.xml and the index database. Copy that folder somewhere safe before you remove anything if you might reconnect this Mac with the same device ID later; without it, your other devices see a reinstalled Syncthing as a new device and every folder share has to be accepted again. This covers the official build from syncthing-macos's GitHub Releases and the Homebrew cask syncthing-app.

Back up the device identity first

1. Open Syncthing from its menu bar icon and let any in-progress sync finish.
2. Check important synced files on another paired device, then copy wanted files outside every Syncthing sync root. Quit the menu bar app and any separate Syncthing service that writes the identity folder before copying its state.
3. In Finder, choose Go › Go to Folder, enter ~/Library/Application Support/Syncthing, and copy the whole folder to a private independent backup outside all sync roots and removal folders, then verify the copy. cert.pem and key.pem are the device identity, config.xml holds your folders and paired devices.

Quit Syncthing and remove the app

1. Quit Syncthing from its menu bar menu. It runs as a menu bar utility with no Dock icon.
2. If you also installed the syncthing command-line service through Homebrew (brew services start syncthing), that is a separate installation with its own background job, homebrew.mxcl.syncthing. Removing the menu bar app does not stop or remove that service, and Mole does not treat that job as this app's login item. Syncthing's documentation gives the same default folder for every Syncthing on macOS, so if that service runs with default settings, the folder above is its identity too.
3. Find Syncthing in Finder's Applications folder and move it to the Trash.

Where the data lives

After quitting, use Shift + Command + G in Finder to inspect each existing path. Once your backup is verified and no other Syncthing installation needs the identity folder, move only the listed items you no longer need to the Trash.

Syncthing’s configuration documentation confirms this Mac default and the identity files; --config, --home or environment variables can change the configuration location, and the database location can also differ. Check your actual configuration before assuming this is the only state folder. The folders you sync are ordinary folders you picked yourself; nothing here touches them.

If you installed it with Homebrew

Mole checks the zap list first: unchecked or shared data, or anything it cannot fully verify, keeps --zap out, and it still removes whatever you selected.

The syncthing-app cask's zap list reaches ~/Library/Application Support/Syncthing-macOS, ~/Library/Caches/com.github.xor-gate.syncthing-macosx, ~/Library/Cookies/com.github.xor-gate.syncthing-macosx.binarycookies and ~/Library/Preferences/com.github.xor-gate.syncthing-macosx.plist. It does not name ~/Library/Application Support/Syncthing, so neither Mole nor a user-run brew uninstall --cask --zap syncthing-app removes the device identity through Homebrew; that folder follows its selection in Mole or your separate manual deletion. The data setting can preselect eligible app-owned data. A user-run --zap still removes every path in the list without looking at Mole's checkboxes.

To remove only the app:

brew uninstall --cask syncthing-app

Check the result

pgrep -il syncthing
launchctl list | grep -i syncthing
ls ~/Library/Application\ Support/Syncthing

• No output from pgrep means no Syncthing process is running. A line means the menu bar app or a separate command-line Syncthing is still open.
• A homebrew.mxcl.syncthing line belongs to the separate Homebrew service, not to this app. On a successful query, no filtered output means no returned session label matched syncthing; this does not rule out differently named or system-level jobs.
• ls listing cert.pem, key.pem and config.xml means the device identity is still on disk, expected if you kept that row unticked. "No such file or directory" means the folder is gone.

What Mole lists

• ~/Library/Application Support/Syncthing starts unchecked with Remove data and settings with apps off. Turning it on can preselect eligible app-owned data; verify your identity backup and uncheck this folder if another Syncthing installation uses it.
• Rows named after the bundle ID com.github.xor-gate.syncthing-macosx, such as its cache and preferences file, are selected by default.
• Mole can also list ~/Library/Application Support/Syncthing-macOS from the cask as a review row, unchecked with the app-data option off; eligible own data can be preselected with it on. The exact bundle-owned cookie file ~/Library/Cookies/com.github.xor-gate.syncthing-macosx.binarycookies can be selected by default when present.
• The Homebrew syncthing service's homebrew.mxcl.syncthing job is never treated as this app's launch item.

What this test covered

On September 19, 2026, Syncthing 2.1.5-1 from the official GitHub Releases download was copied into Applications, opened once, and uninstalled with Mole Preview build 277 with Full Disk Access granted, in a batch of ten apps. ~/Library/Application Support/Syncthing, holding config.xml and the certificate and key, was listed as an unticked review row and stayed on disk. The app ran from the menu bar and used too little memory to get its own row on Mole's Status page. No folders were shared, no remote devices were paired, and neither the Homebrew cask nor the command-line service was tested.