Share Secrets Securely
Maximum Security gives you a live browser-to-browser session secured by authenticated X3DH-style setup plus ML-KEM-768 hybrid key agreement. Team Split brings threshold cryptography — previously the domain of HSMs and enterprise key vaults — entirely into your browser.
Browser-side encryption. Trust-minimized architecture. Storage behavior depends on the mode you choose.
Also available as a Firefox extension
Open Anytime
Standard mode: AES-256-GCM, recipient opens within 15 min up to 30 days
No Server Storage (P2P Mode)
Maximum Security: browser-to-browser P2P, so the secret payload is not stored server-side in this mode
Hybrid Post-Quantum
ML-KEM-768 (NIST FIPS 203) hybrid key agreement in Maximum Security mode to reduce harvest-now-decrypt-later risk
Team Split
Shamir's Secret Sharing: require 2-of-3 or 3-of-5 approval before anyone can read the secret
Security & Privacy First
Browser-side cryptography with explicit, mode-specific storage and trust boundaries.
X3DH-style + ML-KEM-768 Hybrid P2P
Maximum Security mode combines authenticated X3DH-style session setup with ML-KEM-768 hybrid key agreement and per-message symmetric ratcheting for short-lived browser-to-browser transfers.
Async Standard Mode
Send a secret without waiting for the recipient. They open it anytime within 15 minutes up to 30 days — encrypted with AES-256-GCM, key never leaves the URL fragment.
One-Time Viewing
Each Standard-mode link is single-use. After the first successful access, its server record is deleted before response; the ciphertext object is removed shortly after on a best-effort basis, with lifecycle deletion as a backstop.
Zero-Knowledge Architecture
During normal Standard-mode operation, the secret endpoint does not receive the URL-fragment decryption key. Cryptographic operations run in the browser. For P2P sessions, compare the safety number with your recipient over an independent channel.
EU Operation & Privacy Controls
Operated from Romania, EU, with core account infrastructure in AWS eu-central-1, consent-gated analytics, and account export/deletion controls. These support privacy obligations but are not a blanket legal-compliance determination.
Delivery Confirmation & Revocation
Know the moment your secret is opened — real-time delivery status in the sender UI. Changed your mind? Revoke any unread secret instantly, even hours after sharing the link.
Secret Request Links & Templates
Generate a request link and ask someone to send YOU a secret — only you can decrypt it. Built-in templates for SSH keys, database credentials, API keys, and Wi-Fi passwords.
Team Split — Shamir's Secret Sharing
Split a secret into N shares with a k-of-n threshold: any 2-of-3 or 3-of-5 holders can reconstruct it, but no single holder can access it alone. 100% client-side, with share material kept out of server storage.
How Secretus Works
Three modes for different threat models. Choose the one that fits your situation.
Write Your Secret
Type your secret and choose an expiry — 15 minutes up to 30 days, or a custom date. AES-256-GCM encryption key is generated randomly in your browser.
Share the Link
A unique link is generated with the encryption key hidden in the #fragment — invisible to our server. Copy it or share via QR code.
Recipient Opens Anytime
The recipient clicks the link whenever they're ready — no scheduling needed. The secret is decrypted locally in their browser.
Link Expires
After the first successful view, the link is invalidated immediately and ciphertext cleanup follows shortly after. During normal operation, the key remains in the URL fragment and is omitted from the secret endpoint request.
Where Secretus Fits
Designed for individuals and teams that need controlled, one-time secret delivery.
Perfect For:
Sharing Passwords & PINs
Securely share login credentials, access codes, and sensitive account information.
Confidential Notes & Links
Send private messages, private voice messages, confidential documents, or secure access links.
Client & Team Onboarding
Safely onboard new clients or team members with temporary access credentials.
Async Sharing
Send now, they open when ready. No scheduling, no simultaneous presence required.
Team Approval Workflows
Distribute API keys, recovery codes, or critical credentials requiring 2-of-3 or 3-of-5 approval before anyone can access them.
Privacy-First Communication
For anyone who values privacy, security, and peace of mind in digital communication.
Key Benefits:
Simple, Transparent Pricing
Every plan starts with a 14-day free trial — full access, no credit card required.
Displayed prices exclude applicable VAT, sales tax, or GST. Your final total is shown before checkout confirmation.
Starter
Async one-time secret sharing for individuals
14-day free trial included
- No plan-based monthly secret quota — rate and abuse limits apply
- Text-only secrets
- ⚡ Standard Mode — AES-256-GCM (estimated 128-bit security under generic Grover model)
- Custom expiry: 15 min to 30 days
- One-time viewing — link invalidated before delivery; cleanup follows
- Mode-specific backend trust boundary
- Secret labels & annotations
- Secret revocation — cancel before opening
- Delivery confirmation — know when opened
- 📬 Secret request links — ask others to send you secrets
- Secret templates — SSH, database, API key, Wi-Fi
- Audit log — 90-day history, JSON & CSV export
- Two-factor authentication (TOTP / MFA)
- Installable PWA — iOS & Android
Pro
Add hybrid P2P for high-security transfers
14-day free trial included
- Everything in Starter
- 🔒 Maximum Security — X3DH-style + ML-KEM-768 hybrid P2P
- No secret-payload storage on the server in P2P mode
- Priority email support — best effort, no SLA
Business
Full suite: files, voice & k-of-n team approval
14-day free trial included
- Everything in Pro
- 👥 Teams — share your plan with up to 5 members
- 🔑 Team Split — Shamir k-of-n threshold
- Text + file + audio attachments (up to 5 MB)
- API keys — up to 5 keys, REST API integration
- 📊 Compliance PDF — evidence for SOC-2, GDPR Art. 30, DORA
- 1-year audit log retention
Need a custom plan for a larger team? Contact us.
Ready to Share Secrets Securely?
Trust-minimized, browser-side encryption for your most sensitive information. Start sharing secrets securely today.