Short answerA zero-knowledge service encrypts data on your device with keys that are never sent to the company. The provider stores only ciphertext, cannot reset your password, and cannot hand readable data to anyone. If a vault can recover your files by email, it is not zero-knowledge.
The test
Ask one question: can the company reset your password and give you your files back?
- If yes, it holds a key or a way to get one. Not zero-knowledge.
- If no, and recovery depends on something only you hold (a phrase, a key file), it probably is.
What the provider still sees
Zero-knowledge protects content, not every trace. A provider may see:
- That you have encrypted data, and roughly how much.
- When it changes.
- Your IP address when you connect.
VaultBolt pads and chunks data to reduce what sizes reveal, never records which vault or unlock you used, and states these limits on its security page.
Where zero-knowledge stops
It protects data at rest on servers and in transit. It doesn't protect a photo you open on an unlocked phone, a screenshot the recipient takes, or a weak password someone guesses.
Frequently asked questions
Is VaultBolt zero-knowledge?
Yes, by design. Files are encrypted on your device, keys never leave it, and there is no account or password reset. Our planned sharing relay stores only ciphertext.
What can a zero-knowledge provider still see?
Usually metadata: that encrypted records exist, their sizes and when they were updated.
