What this tool does
File Hash Calculator reads an ArrayBuffer from a file input and calculates the selected digest in the browser. Files are not uploaded or processed by fetch, XHR, or third-party APIs; larger files may require more browser resources to read completely into memory.
- Supports SHA-256, SHA-512, and can use local MD5 implementation within the project.
- Status is displayed during calculations and prevents repeated starts of the same task.
- MD5 is only suitable for compatibility check, and SHA-256 or SHA-512 is preferred for security integrity check.
How to use it
- Click "Choose File" and select a local file.
- Confirm the displayed file name, size and type.
- Select the algorithm and click "Calculate Hash".
- After the calculation is completed, copy the summary for comparison.
Common uses
- Verify the downloaded file against the SHA digest provided by the publisher.
- Confirm whether the byte contents of the two local files are consistent.
- Record reproducible integrity fingerprints for your build products.
Privacy and security
The selected file is only read and hashed in the browser and will not be uploaded to the server; large files may occupy more memory when using Web Crypto.
File Hash Calculator Features
Select a local file and calculate SHA-256, SHA-512 or MD5 within the browser, no upload required. Useful for everyday development and debugging; results can be reviewed, copied, or downloaded immediately.
FAQ
Will the file be uploaded to the server?
No. Files are only read and evaluated by the current browser tab.
Why do large files require more memory?
Web Crypto digests usually receive a full ArrayBuffer, so the browser may need to keep the entire file in memory.
Which algorithm should be chosen?
SHA-256 is preferred for general integrity checks; SHA-512 provides a longer digest, and MD5 is only used for compatibility with older systems.
Will the results be the same every time for the same file?
Yes. As long as the file bytes and algorithm are the same, the digest is deterministic.