# File upload

> Methods for adding files, multipart chunking for large objects, and local integrity verification.

MMW Cloud allows uploading all common file formats within your active storage quota.

## Upload methods

The web cabinet at https://app.mmwcloud.tech provides two ways to add files:

- Upload File button: located at the top of the Files view. Opens your operating system file picker.
- Drag and drop: drag one or more files directly from your desktop file manager into the browser window.

## Small file transfers

Files smaller than 8 MiB transfer in a single direct request. The browser computes an SHA-256 checksum, receives an authorized upload link, and delivers the binary payload directly to storage.

## Multipart upload for large files

Objects measuring 8 MiB and larger use multipart chunking:

1. File splitting: the browser splits the payload into fixed-size chunks.
2. Local hash computation: an SHA-256 checksum is calculated locally on your computer or phone prior to transmission.
3. Chunk delivery: fragments upload over an encrypted channel. The server confirms each received block with an ETag token.
4. Assembly: once all parts are transferred, the storage backend finalizes the object and updates its state to ready.

A progress indicator displays upload completion percentages in real time.