Mac Sai
Mac Sai is a free, open-source cleaner, optimizer, and malware scanner for macOS.
What Mac Sai is
Mac Sai is a free, open-source cleaner, optimizer, and malware scanner for macOS. Smart Scan runs cleanup, protection, and performance modules together, while System Junk checks 16+ categories. Its malware scanner uses curated signatures with Quick, Balanced, and Deep scan options; the project states that it is not an antivirus. Privacy tools clear history, cookies, and cache in Safari, Chrome, and Firefox while preserving Safari bookmarks. App management includes uninstalling with leftover detection, resetting apps to defaults, reviewing extensions, and checking Sparkle appcast version information. Space Lens visualizes disk usage, Large & Old Files locates files over 50 MB, and Duplicates can consolidate files using APFS clones. Mail Attachments finds cached items from Apple Mail, Outlook, and Spark. The maker says there are no analytics, crash reporter, trackers, or telemetry server connection; optional network paths are for update checks. Deletion safeguards include trash-first handling, protected-path blocks, exclusions, and a dry-run preview. Mac Sai requires macOS 14 or later and is offered through Homebrew, a DMG, a one-line installer, or source build.
Good
- Smart Scan combines cleanup, protection, and performance modules.
- Privacy cleanup preserves Safari bookmarks.
- Disk tools visualize usage and find files over 50 MB.
- Maker says telemetry is absent; update checks are optional.
Watch out
- Requires macOS 14 or later.
- Malware scanner is explicitly not an antivirus.
- Several modules require Full Disk Access.
Who it suits
Mac Sai suits Mac users looking for cleanup, disk tools, app management, privacy controls, and malware scanning in one free utility. Its malware module is not presented as an antivirus.
Verdict
Mac Sai offers a broad set of Mac maintenance tools at no cost, with deletion safeguards and no telemetry connection according to its maker. Note the macOS 14+ requirement, and that protected-area scans require Full Disk Access.
Plans and prices
From Mac Sai's own pricing page, checked 4 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Mac Sai | Free | Free forever · no subscription · no in-app purchases |
The facts
Each one read from Mac Sai's own pages, with the date it was checked.
Where it runs
- Apple notarization
- The maker says Mac Sai is signed with an Apple Developer ID and notarized by Apple.checked 4 Oct 2026
- App management
- The app includes an uninstaller with leftover detection and reset-to-defaults, an extensions reviewer, and an updater that reads Sparkle appcast version information.checked 4 Oct 2026
What it does
- Cleanup
- Smart Scan runs cleanup, protection, and performance modules together, while System Junk scans 16+ categories.checked 4 Oct 2026
- Deletion safeguards
- The maker describes trash-first deletion, protected-path blocks, symlink and TOCTOU checks, excluded folders, and a dry-run preview.checked 4 Oct 2026
- Disk tools
- Space Lens visualizes disk usage, Large & Old Files finds files over 50 MB, and Duplicates can consolidate files using APFS clones.checked 4 Oct 2026
- Full Disk Access
- Mail Attachments, Privacy, and Malware modules require Full Disk Access to scan protected areas.checked 4 Oct 2026
- Install and support
- The project offers installation through Homebrew, a DMG, a one-line installer, or source build, and invites contributions through GitHub pull requests.checked 4 Oct 2026
- Integrations
- Mail Attachments finds cached attachments from Apple Mail, Outlook, and Spark; the Updater checks apps through their Sparkle feeds.checked 4 Oct 2026
- License
- Mac Sai is distributed under the BSD 3-Clause license.checked 4 Oct 2026
- Privacy tools
- The Privacy module cleans Safari, Chrome, and Firefox history, cookies, and cache, while leaving Safari bookmarks untouched.checked 4 Oct 2026
- Protection
- Its malware scanner uses curated signatures at Quick, Balanced, and Deep scan depths, and the project says it is not an antivirus.checked 4 Oct 2026
- Purpose
- Mac Sai is an open-source Mac cleaner, optimizer, and malware scanner.checked 4 Oct 2026
- System requirement
- The comparison section lists macOS 14+; building from source requires Swift 6 (Xcode 16+).checked 4 Oct 2026
- Telemetry
- The maker states Mac Sai has no analytics, crash reporter, trackers, or server connection for telemetry; its listed network paths are optional update checks.checked 4 Oct 2026
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