Secure File Upload – XChaCha20 E2E, Zero-Knowledge
The only secure upload is an encrypted upload. Every file is encrypted in your browser with XChaCha20-Poly1305 before it ever reaches our servers. We technically cannot read what you upload.
The only secure upload is an encrypted upload. Every file is encrypted in your browser with XChaCha20-Poly1305 before it ever reaches our servers. We technically cannot read what you upload. Legal documents, medical records, financial data, source code — when you upload sensitive files, you need to be certain no one else can access them. cryptfiles.cloud delivers technical certainty, not just policy promises.
Why cryptfiles.cloud for Secure file upload
XChaCha20 End-to-End Encryption
Every file is encrypted client-side with XChaCha20-Poly1305 before it ever reaches our servers. Only you hold the key.
Zero-Knowledge Architecture
We only store encrypted ciphertext. Your plaintext content is technically inaccessible to us – by design.
Maximum Privacy by Design
No third-party tracking without consent, no metadata sales, no profiling. Your uploads belong to you.
EU Servers – Stockholm, Sweden
All data stays in the European Union on servers in Stockholm. No critical data transfer to third countries, no US Cloud Act exposure.
For sensitive documents, confidential data, and private content
Legal documents, medical records, financial data, source code — when you upload sensitive files, you need to be certain no one else can access them. cryptfiles.cloud delivers technical certainty, not just policy promises.
Secure file upload - up and running in minutes
Key generated locally
Your browser generates a unique encryption key. It never leaves your device.
Encrypted before upload
XChaCha20-Poly1305 encrypts your file locally. Only ciphertext is transmitted.
Key in the share link
The key is in your link's URL fragment (#) — never sent to the server per HTTP spec.
Questions about Secure file upload
No. HTTPS only secures the transport. The server operator can still read your file. True security requires end-to-end encryption where the key never leaves your device.
We can only provide encrypted ciphertext — without your key, it's useless. We operate under EU law, and even under court order, we have nothing readable to hand over.
Yes. The WebCrypto API runs in all modern browsers on iOS and Android. Full E2E upload and sharing from any smartphone.
No hard per-file limit. Our resumable chunked upload handles very large files. Practical limits depend on your available storage quota.
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Jetzt kostenlos starten
10 GB kostenloser Speicher, Ende-zu-Ende-verschlüsselt, EU-Server, optionaler Revenue Share.
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