Skuld
Sync your files. Your way.
A native file synchronization tool for macOS. Local, SMB, SFTP, and cloud. Simple and reliable.
Download Free · macOS 15+ · Apple Silicon Support this appMirror, Update, or Two-Way.
Mirror replicates source to target with deletions. Update copies new and changed files only. Two-Way syncs both directions, conflicts are resolved by hand.
Local, SMB, SFTP, and cloud in one app.
Synchronize between local folders, SMB network shares, SFTP servers, and cloud storage: Hetzner Storage Box, S3, Backblaze B2, WebDAV, through built-in rclone. Import your existing rclone remotes in one click. Mix and match any source and target type.
See what will change before it happens.
Two-step workflow: compare first, then sync. Visual tree diff shows every file that will be created, updated, or deleted, and a confirmation sums up copies and deletions before anything runs.
Everything you need
Smart Comparison
Compare by time and size, or by content hash (SHA-256) for precise change detection.
Flexible Filters
Include/exclude patterns with glob syntax. Global filters or per-folder-pair rules. Skip node_modules, .git, and more, or keep only the latest dated version of your backups.
Jobs and Groups
One job, multiple folder pairs, each one on or off. Sort jobs into groups and run several at the same time.
SFTP and Cloud
SFTP servers with SSH Agent, Keychain, or key file, and the server's host key checked. Cloud storage through built-in rclone, no command line.
Encrypted Backups
Encrypted remotes encrypt file contents and names before upload: the host sees nothing. rclone-compatible, so you can restore from any machine.
Verified Shares
Before reading a network share, Skuld checks it is the right server and the right share. An unmounted or swapped share stops the job instead of emptying the target.
Sync Tracking
Time left and end time, progress on the Dock icon, a notification when done. What failed can be sent again from the report, without comparing everything again.
Native macOS
Built with Swift and SwiftUI. Lightweight, fast, no Electron. Apple Silicon native.
Available Languages
Your files. Your Mac. Nothing else.
No data collection, no analytics, no telemetry. Skuld only connects to the servers you configure. All credentials stored in macOS Keychain. Requires macOS 15 Sequoia or later.