The short version
Webcam face match
Fast, and good against casual access. Not a defence against a video replay or a mask.
Hello / Touch ID
Dedicated biometric hardware. Use it when the threat is more than a curious person.
Encrypted files
XChaCha20-Poly1305 with a random 256-bit key. Your face is never the key.
FaceLock is a lock that sits on top of your Windows or macOS sign-in. It guards your laptop when it wakes, guards the apps you choose, and encrypts the files, folders and photos you choose. Everything runs on your laptop.
Face unlock and its limits
An ordinary laptop webcam sees a flat colour image. FaceLock enrols your face from seven angles, then matches several frames in a row and asks for a blink. That stops a printed photo and most phone screens.
A video replay of you, or a good enough mask, can fool any ordinary RGB webcam, whichever software is reading it. So FaceLock treats webcam face match as a convenience gate: a fast, pleasant way to keep casual hands off your things. It isn’t cryptographic proof that you’re you. If you need that level, use Strict mode.
Unlock methods
| Method | Strength | Notes |
|---|---|---|
| Face (webcam) | Convenience | 7-angle enrolment, multi-frame match, blink check. |
| Windows Hello / Touch ID | Strong (Strict mode) | IR face camera or fingerprint sensor, handled by the operating system. |
| PIN | As strong as the PIN | At least 6 digits. Stored only as an Argon2id hash. |
| Recovery key | Strong | 24 characters, shown once at setup. Always opens your vault. We never see it. |
How files are encrypted
- Real encryption, never hiding. Locking
photo.jpgreplaces it withphoto.jpg.flk, an encrypted file. Locking a folder encrypts every file inside it. - Cipher: XChaCha20-Poly1305 (authenticated encryption) in 64 KiB chunks using the STREAM construction, so a file can’t be truncated, reordered or tampered with undetected.
- Per-file random nonce. The original file name is encrypted inside the header.
- Crash-safe. FaceLock writes the ciphertext to a temporary file, flushes it to disk, decrypts it again and checks it against a BLAKE3 hash of the original. Only then does it rename it into place and delete the plaintext.
- Opening a locked item decrypts it into a temporary session folder. When you close it, go idle or put the laptop to sleep, FaceLock re-locks it and wipes the temporary copy. While a file is open, its plaintext exists on disk, just as it would with any editor.
Keys and secrets
- Your files are encrypted with a random 256-bit vault key. The vault key is kept in your operating system’s keychain (Windows Credential Manager or the macOS Keychain).
- Your face is never a key. Face, Hello / Touch ID and PIN only decide whether FaceLock releases the vault key.
- Your face template is stored encrypted with the vault key. Camera frames are never written to disk. The one exception is the optional intruder photo, which is encrypted too.
- The recovery key can always open the vault, so uninstalling, a broken camera or a new laptop never strands your data. Keep it safe: anyone holding it can open your vault, and we can’t reset it for you.
How each lock works
- Lid / wake lock: on resume from sleep, lid open, screen unlock or app start, FaceLock shows a full-screen, always-on-top cover on every display until you verify. It doesn’t replace the OS sign-in screen; that would need a Windows Credential Provider or a macOS SecurityAgent plugin, which we have deliberately not built.
- App lock: when a locked app launches or comes to the front, FaceLock suspends its process (Windows: suspends its threads; macOS:
SIGSTOP) and covers it. Verify, and it resumes. Cancel, and it’s closed. Core system processes can never be locked, so you can’t lock yourself out of your own desktop. - Walk-away lock (optional): while you’re unlocked, FaceLock checks the camera about once a second. If no face appears for the time you set, it locks the operating system.
- Shoulder-surfer alert (coming in a later version): if a second face appears while a locked app is open, FaceLock will blur the app.
- Intruder photo (optional): after two failed attempts, FaceLock saves an encrypted camera frame, the time and what was tried, and shows them at your next successful unlock.
- Panic hotkey: Ctrl+Alt+L (⌘+⌥+L on Mac) locks everything at once.
What it protects against
| Situation | FaceLock |
|---|---|
| Someone opens your laptop while you’re away | Covered: lid / wake lock |
| A colleague or family member opens your chats, mail or photos | Covered: app lock and file lock |
| Your disk, a backup or a USB copy of locked files is read elsewhere | Covered: files are encrypted |
| Someone glances over your shoulder at a locked app | Not yet: the shoulder-surfer alert is coming in a later version |
| A video replay or mask aimed at the webcam | Not reliably. Use Strict mode (Hello / Touch ID) |
| Someone technically skilled, using your laptop while your Windows or Mac account is signed in and unlocked | Not fully covered. FaceLock keeps its file key in your operating system’s keychain so your face can release it; a person at your unlocked desktop could pull it out with the right tools. Lock your computer when you step away, or turn on walk-away lock |
| Malware running as you while you’re unlocked | Not covered. Nothing on your laptop can be, once you’ve unlocked it |
| Someone who knows your PIN or holds your recovery key | Not covered. Guard them like passwords |
| An administrator who stops FaceLock | App and lid locks stop. Locked files stay encrypted |
FaceLock adds to your operating system’s security; it doesn’t replace it. Keep a strong account password, keep your system updated, and turn on full-disk encryption (BitLocker or FileVault) as well.
What touches the network
Your face, camera frames, files and the list of things you lock never leave your laptop. The face models ship inside the app. The only network traffic is the licence check with facelock.io, which sends your licence key, a device ID, your laptop’s name and its operating system, so one licence maps to one laptop. Licences are signed and checked offline, so FaceLock keeps working without a connection. See the privacy policy for the full detail.
When a licence expires, protection pauses until it’s renewed, but already-locked files, folders and photos always stay openable with your face, Hello / Touch ID, PIN or recovery key. Your data is never held hostage.
Reporting a problem
If you think you’ve found a security issue, please email [email protected] with “Security” in the subject. Include steps to reproduce if you can. We’ll reply, keep you updated, and credit you if you’d like. Please give us a reasonable chance to fix it before you publish. Our security.txt has the same details.