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Preview of Secretus — Share a Secret

Secretus — Share a Secret by Secretus

Share a one-time, end-to-end encrypted secret from anywhere in your browser. Zero-knowledge: the decryption key never leaves your device.

Some features may require paymentSome features may require payment
Available on Firefox for Android™Available on Firefox for Android™
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Paste a password or API key, set an expiry, and create a one-time link — encrypted in your browser before anything is uploaded.The link is ready to share. It opens exactly once, then the ciphertext is destroyed. The decryption key rides in the link fragment, which never reaches our servers."My secrets" tracks what you created from this browser: see when a link was opened, and revoke any unopened one instantly.Sign in with Google, or with email and password over SRP — your password never leaves your device.
About this extension
Share a secret from anywhere in your browser — as a one-time, end-to-end encrypted link that self-destructs after it's opened.

Secretus is built zero-knowledge: your secret is encrypted on your device before anything is uploaded, and the decryption key travels only inside the link you share (in the URL fragment, which browsers never send to servers). Our servers store ciphertext they cannot read. Ever.

About the data permissions Firefox shows you
Firefox lists "personal communications" because your encrypted secrets pass through our servers on the way to whoever you share them with. We cannot read them — they arrive as ciphertext and the decryption key never reaches us. "Authentication info" covers signing in to your account.

WHAT YOU CAN DO
* Share a password, API key, or note as a one-time link in seconds
* Right-click any selected text → "Share selection securely"
* Attach files — encrypted on-device before upload (Business plan)
* Set an expiry: 15 minutes to 30 days
* Label your secrets and track them in "My secrets": see when a link was opened, and revoke unopened links instantly
* Keyboard shortcut: Ctrl+Shift+S (⌘⇧S on Mac)

SECURITY, FOR PEOPLE WHO CHECK
* AES-256-GCM encryption in the popup via the browser's native WebCrypto
* The decryption key lives only in the link fragment — never sent to, stored by, or visible to Secretus servers
* Every link works exactly once, then the ciphertext is destroyed
* Password sign-in uses SRP (Secure Remote Password): your password never leaves your device — not even to us
* No analytics, no tracking, no browsing-history access. The extension reads a page only when you explicitly share a selection from it
* Works only in regular windows (disabled in private browsing by design)

Requires a Secretus account: a 14-day free trial, then a paid plan. See secretus.app/offer.

Open the link on any device — no extension or app needed to receive a secret.
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Permissions and data

Optional permissions:

  • Access your data for api.eu.secretus.app
  • Access your data for secretus-eu-1765116481.auth.eu-central-1.amazoncognito.com
  • Access your data for cognito-idp.eu-central-1.amazonaws.com

Required data collection, according to the developer:

  • Authentication information
  • Personal communications
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Version
1.0.1
Size
111.79 KB
Last updated
4 days ago (Jul 23, 2026)
Related Categories
  • Privacy & Security
  • Social & Communication
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Tags
  • privacy
  • security
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