---
id: data-transfers.is-a-large-download-checked
url: https://storagestudio.us/faq/data-transfers/is-a-large-download-checked
category: "Data Transfers"
subcategory: "Downloads and large files"
question: "How do I know a large download finished correctly and isn't corrupted?"
alt_questions:
  - "verify downloaded file"
  - "is the download complete and verified"
  - "download integrity check mac"
  - "corrupted download storage studio"
  - "assembled file came out the wrong size"
short_answer: "Each piece is checked as it arrives and the finished file is checked again; the log says “…is complete and verified”. If the assembled file is wrong it isn't kept and nothing at the destination is overwritten."
tags: ["verification", "download", "integrity"]
related: ["https://storagestudio.us/faq/data-transfers/large-downloads-resume-where-they-left-off", "https://storagestudio.us/faq/data-transfers/a-piece-couldnt-be-downloaded"]
applies_to: "app>=4.16"
last_reviewed: 2026-10-01
---

# How do I know a large download finished correctly and isn't corrupted?

Large downloads are checked before they're marked finished. Each piece is checked as it arrives, a piece that didn't arrive intact is fetched again, and when everything is put together the result is checked again. The log ends with *"…is complete and verified"* when all is well.

If the assembled file isn't right — for example *"The assembled file came out the wrong size, so it wasn't kept"* — the faulty file isn't kept and nothing at the destination is overwritten.

If the website publishes its own checksum for the file, you can also compare that yourself for extra peace of mind.

Related: [Large downloads that resume](https://storagestudio.us/faq/data-transfers/large-downloads-resume-where-they-left-off)