Send files securely — only the recipient can open them.

Files are encrypted in your browser before upload. Share a secure link with expiration and optional identity check.

Encrypted before upload Optional secret question One-time or expiring access

Encrypted Upload

Seal files in mbox

Drop one or more files, choose how long the link should stay valid, and optionally protect access with a secret question.

Add files (up to 5MB)

Max 5 files, up to 5MB total.

    • Encryption happens in your browser
    • The key is never sent to our server
    • Messages disappear automatically
    • No account required

    What do you want to send?

    Send sensitive data that disappears.

    Share passwords, files, and private notes using encrypted links that expire automatically.

    Secure Message

    • Encrypted before sending
    • Optional password protection
    • Expiration control
    Send Secure Message

    One-Time Note

    • Read once only
    • Auto delete after reading
    • No recovery
    Create Note

    Secure File Sharing

    • Files encrypted in your browser
    • Share via secure link
    • Auto expiration
    Send Files

    Generate & Send Password

    • Generated locally
    • High entropy
    • Secure sharing
    Generate Password

    Secure file drop with Zero-Knowledge protection

    Secure File Drop lets you hand over documents, archives, and sensitive files through an encrypted link without leaving readable copies on the server.

    A safer way to send files online

    Traditional file sharing tools focus on convenience, but they often keep files stored in plain service-controlled workflows for longer than necessary. Secure File Drop is built for situations where privacy matters more than collaboration features.

    The sender drops files directly in the browser, the payload is encrypted before upload, and the recipient opens a single secure link. You can also set a short validation window or one-time access to reduce exposure.

    How encrypted file delivery works

    Each selected file is encrypted on the client side before it is transmitted. The server stores only encrypted blobs and metadata needed to deliver the package, but not the key fragment required to decrypt it.

    Because the key remains in the link fragment, the platform cannot inspect the file contents. This is the practical benefit of a Zero-Knowledge file transfer model for ad hoc document sharing.

    • Client-side encryption Files are encrypted in the browser before upload so the server only receives unreadable ciphertext.
    • Controlled expiration Choose one-time access or a defined retention window to reduce how long the link stays valid.
    • Secret question option Add an extra identity check before decryption when only the recipient should know the answer.

    When secure file drop is useful

    This workflow is useful for finance teams sending statements, agencies sharing signed documents, developers handing off configuration archives, and IT teams transferring credentials or recovery bundles to a single recipient.

    It is also a cleaner approach when you do not want files to remain searchable in email inboxes, chat history, shared drives, or ticketing systems.

    Key benefits

    Encrypted before upload

    Protection starts in the browser, not after the file reaches the service.

    Short-lived access

    Use expiration controls to avoid long-term file exposure.

    Extra recipient verification

    A secret question can reduce accidental or unauthorized access to the link.

    Simple handoff

    Send one secure link instead of coordinating accounts, portals, or shared folders.

    No account required

    The sender can encrypt and deliver a file package immediately without registration.

    Better privacy posture

    File contents remain unreadable to the platform because the decryption key is not sent to the server.

    Secure File Drop FAQ

    What is a secure file drop?

    A secure file drop is a way to upload files and share them through a protected link instead of sending attachments in plain email or chat. In mbox, files are encrypted in the browser before upload and can be shared with one-time or time-limited access.

    How is this different from Google Drive, Dropbox, or WeTransfer?

    Typical file-sharing platforms are designed for storage and collaboration. Secure File Drop is designed for short-lived confidential delivery. The file package is encrypted before upload, the service does not receive the decryption key fragment, and access can expire automatically.

    Are files encrypted before they are uploaded?

    Yes. Files are encrypted locally in the browser before they are sent to the server. The stored payload is unreadable without the key fragment contained in the final link.

    Can I protect file access with a secret question?

    Yes. You can add a secret question that the recipient must answer before the encrypted file package is revealed. This adds an extra identity check beyond possession of the link alone.

    Can I make the file link expire after one view?

    Yes. You can choose a one-time access option or a time-based expiration window. This is useful when documents should only be available for a short period.

    Who should use secure file drop?

    It is useful for legal, finance, HR, IT, agencies, and software teams that need to deliver contracts, exported data, credentials, signed PDFs, or incident files without leaving permanent readable copies in common communication tools.

    Does the server see my file contents?

    No. The server stores encrypted data, but the decryption key fragment is not sent with the request. That means the platform can deliver the package without being able to inspect the file contents.

    Is secure file drop suitable for sensitive business documents?

    Yes. It is particularly suitable for short-lived delivery of invoices, statements, reports, signed contracts, certificates, and administrative exports when you want better control over who can access them and for how long.