Free tool · Runs in your browser
File hash calculator: SHA-256, SHA-1 and SHA-512
Choose a file to get its SHA-256, SHA-1 and SHA-512 hashes, then paste a published hash to check they match. The file is hashed on your device with your browser's built-in cryptography and is never uploaded, which matters most for exactly the files you are unsure about.
The file is hashed on this device. It is never uploaded.
How it works
A hash is a fixed-length fingerprint calculated from every byte of a file. Change one byte and the hash changes completely, so a matching hash means the file is identical to the one the hash was published for.
What to use a file hash for
- Checking a download: software sites publish SHA-256 checksums. If yours matches, the file was not damaged or swapped.
- Looking up a suspicious file: search the SHA-256 on a threat intelligence site such as VirusTotal to see whether it is known, without uploading the file itself.
- Sharing an indicator: analysts share hashes of malware so others can hunt for the same file.
The same thing on the command line
- Windows (PowerShell):
Get-FileHash .\file.zip -Algorithm SHA256 - macOS:
shasum -a 256 file.zip - Linux:
sha256sum file.zip
MD5 is not offered because it is broken: two different files can be made to share an MD5 hash. Use SHA-256. Hashes are the first step of malware analysis, and the simplest kind of signature in how antivirus detects malware.
The M-Learn app
Want to understand what the tool is checking?
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