Documents
Encrypt Excel Workbook Files Online
Modern Microsoft Excel format with support for larger datasets and features.
Encrypt Your .xlsx File Now
Free • No account • AES-256-GCM • Auto-deletes in 48h
Upload & Encrypt .xlsx →Advertisement
How to encrypt a Excel Workbook file
1.Click the upload button above and select your .xlsx file. Files up to 500MB are supported.
2.FastDDL generates a random AES-256-GCM encryption key and encrypts your Excel Workbook in your browser before upload. The server never sees the password.
3.You receive a shareable URL and a one-time decryption password. Send the link to your recipient through any channel.
4.The recipient enters the password on the download page to decrypt and download the Excel Workbook file. The file auto-deletes after 48 hours.
Why encrypt Excel Workbook files?
Excel Workbook files are commonly used for spreadsheets, financial models, reports. When shared unencrypted, they can be intercepted, scanned, or accessed by anyone with the link — including the file sharing service itself.
FastDDL uses zero-knowledge AES-256-GCM encryption, meaning:
- Your xlsx file is encrypted before it leaves your device
- The encryption password is never stored on the server
- Even FastDDL operators cannot decrypt your file
- The encrypted file is stored on Cloudflare R2 and auto-deletes
- Tampering is detected automatically via authenticated encryption
Zero-Knowledge
Server never holds your decryption key
AES-256-GCM
Military-grade authenticated encryption
Auto-Delete
Files vanish in 1h–48h, no trace