# What Is a SHA-256 File Hash?

SHA-256 is a fixed-length cryptographic digest produced from file content.

## Why Virusis generates hashes

The UI hashing service generates hashes when a file is selected in order to:

* identify the same sample again
* search for an existing scan record
* carry a stable sample identity through sharing and result flows

## Where it appears in the product

* in the pre-scan existing-result check
* in the checksum selector on the result screen
* in the PDF report

## Why the file name is not enough

Because a file name can change while the content hash stays the same. Virusis can still recognize the same sample even if it is uploaded under different names.

## Short conclusion

Inside Virusis, SHA-256 is not just a technical field. It is the core sample identity for deduplication, lookup, and reporting.


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