Feature01
Why multipart changes reliability
A single long request ties success to one uninterrupted connection. TransferSize creates an upload session, sends bounded parts, records completed parts, and finalizes only when the complete object can be verified.
Feature02
Recovery is part of the protocol
Parts are idempotent and retryable. The uploader can switch between direct and proxy delivery when needed, adapt concurrency, and continue from confirmed progress rather than guessing what reached storage.
- Independent retry for failed parts
- Cancellation support
- Live progress, speed, and ETA
Feature03
What resumable does not mean
Do not close the browser assuming every unfinished session will survive indefinitely. Keep the tab open when possible, reconnect, and let the interface confirm completion before sharing the resulting link.
Edge cases
Before the handoff
Will one failed part corrupt the file?
The service uses a per-part integrity value and verifies the final uploaded size before completing the transfer.
Does TransferSize load the whole file into browser memory?
The upload protocol is designed to stream bounded parts rather than buffer the entire large file.