Every word encrypted with AES-256 before it leaves your device. Not even we can read your work. Write freely — from anywhere.
A full-featured editor with Markdown, rich formatting, focus mode, tables, and task lists. Everything you expect from a premium editor — with one difference: every character is encrypted in your browser before being sent anywhere. Our servers never see what you write. Export to PDF, Word, or Markdown anytime.
Upload PDFs, images, contracts, and any file — everything is automatically encrypted before leaving your device. Organize with hierarchical folders, preview directly in your browser, and rest assured that not even we know the name of what you stored. Up to 5GB on the Pro plan.
Send and receive end-to-end encrypted messages with other Writtt users. Perfect for sharing text feedback, discussing sensitive contracts, or chatting with clients — without anyone, not even us, having access to the content. Real privacy, no middlemen.
A full-featured editor with Markdown, rich formatting, focus mode, tables, and task lists. Everything you expect from a premium editor — with one difference: every character is encrypted in your browser before being sent anywhere. Our servers never see what you write. Export to PDF, Word, or Markdown anytime.
Upload PDFs, images, contracts, and any file — everything is automatically encrypted before leaving your device. Organize with hierarchical folders, preview directly in your browser, and rest assured that not even we know the name of what you stored. Up to 5GB on the Pro plan.
Send and receive end-to-end encrypted messages with other Writtt users. Perfect for sharing text feedback, discussing sensitive contracts, or chatting with clients — without anyone, not even us, having access to the content. Real privacy, no middlemen.
Zero-Knowledge means exactly that: zero knowledge. Writtt Pro is engineered so our servers never have access to the content of your files, texts, or messages. Not even if we wanted to.
It's an encryption model where the key that unlocks your data exists only in your browser. The server stores encrypted blocks that, without your Master Password, are indistinguishable from random noise. No employee, hacker, or government can read the content.
Every text, file, and message is encrypted with AES-256-GCM directly on your device, before any upload. Keys are derived from your password via Argon2id with 64 MB of memory, making brute-force attacks infeasible. The server only receives opaque blocks — never the original content, not even the file names.
It means that even in case of a breach, data leak, or court order, your data remains unreadable. There is no backdoor, no master key on our end, and no technical possibility of reversing the encryption without your personal password.
When we say 'Zero-Knowledge', we're not using a slogan. We're referring to a formal cryptographic protocol, defined by three mathematical properties that guarantee it is impossible to access your data without your password. These are the three laws that govern our engineering:
If you have the correct password, the system will always authenticate you successfully. There are no false negatives — the protocol guarantees the rightful owner is never locked out.
If someone does not have the password, it is mathematically impossible to fool the system. No matter the attacker's computational power — the probability of forging access is less than 1 in 2²⁵⁶.
Throughout the entire authentication process, the server learns absolutely nothing about your password. It verifies that you possess it without ever receiving it. This is how your data remains invisible to us.
Everything described above isn't magic — it's irreversible mathematics. The protocol governing Writtt Pro's authentication operates with 256 cryptographic rounds (256-bit), where the chance of a fraudulent bypass is 1 in 115 Quattuorvigintillion — a number remarkably close to the total atoms in the observable universe. Brute-forcing this barrier would take longer than the age of the cosmos.
Writtt Pro operates under an absolute principle: unencrypted data never touches our disks. Every keystroke and file upload is exclusively sealed within your browser's isolated memory. We operate 'blind' databases that merely warehouse scrambled noise. This is what makes us a true Zero-Knowledge ecosystem.
We also guarantee Zero Telemetry inside your documents. The only things we manage are validating your access pass and maintaining your subscription status.
In an era where major corporations silently change their terms of service to devour authorial texts and train AIs, Writtt Pro stands as a counter-culture. We take care of the software; mathematics takes care of your intellectual property.
Join a community that doesn't compromise on privacy, choosing Writtt Pro to keep their ideas completely safe. Your words. Your encryption key. Your privacy
Create Free VaultGet started — essential access with E2E encryption.
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