[ABOUT HASH FILE ONLINE]

Hash File Online was created with a simple but important mission: provide a powerful, reliable file hashing tool that respects your privacy absolutely. In an age where most online tools require uploading your files to remote servers, we took a different approach.

Every hash calculation on this website happens entirely in your web browser. Your files never leave your computer. There are no uploads, no server processing, and no data retention. This isn't just a feature—it's a fundamental design principle that guides everything we build.

We believe that verifying file integrity shouldn't require trusting a third party with your data. Whether you're checking the authenticity of a downloaded software package, verifying backup integrity, or conducting security audits, your files should remain yours alone.

Hash File Online is built and run by one person, Vladimir Lorentz, an independent developer based in Lyon, France. It is a personal project, not a company: there is no team, no investor and no account system. The French edition of the same tool is published at Empreinte Numérique, and its sister site CryptFile.Online does browser-side file encryption.

I have been working as a software engineer for 15 years, building web applications and the tooling around them.

I built it because most online hash calculators ask you to upload the file first, which is the opposite of what you want when the file is evidence, a private document or a large download you are trying to verify. Here the browser does the work and the file stays on your device.

You can reach me through the contact page, by email at vladimir.lorentz@gmail.com, or on LinkedIn. The publisher details are in the legal notice.

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  In your browser, in WebAssembly. All six algorithms (MD5, SHA-1, SHA-256, SHA-384, SHA-512 and BLAKE2b) come from hash-wasm, an open-source library that compiles reference implementations of these functions to WebAssembly. The algorithms are the standard ones: MD5 is defined in RFC 1321, the SHA family in NIST FIPS 180-4 and BLAKE2b in RFC 7693, so a hash from this page matches the one any other correct tool produces for the same bytes.
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  Streamed in 4 MB chunks. The file is read piece by piece and each piece is fed to the hash function, so memory use stays flat and there is no size limit: multi-gigabyte videos and disk images work, they just take longer. When you pick "MD5 + SHA-256", both digests are computed from the same single read of the file.
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  Reports are generated locally too. PDF, CSV, JSON, HTML and TXT reports are built in the page from the results you see on screen, with the file name, size, path inside a folder, algorithm, hash value and the date of calculation.
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  Check it yourself. You do not have to trust this page. Hash the same file with certutil -hashfile file SHA256 or Get-FileHash on Windows, shasum -a 256 on macOS or sha256sum on Linux: the values must be identical. To confirm that nothing is uploaded, open your browser's developer tools, switch to the Network tab and hash a file — no request carries its contents.

The guides and landing pages on this site are written by me from the standards above, the documentation of the operating-system tools they mention, and the questions people actually search for. Where a page touches on law (for example the hash value certificate used with Indian electronic evidence), it explains the technical side and points you to the official text; it is not legal advice.

Here is exactly what happens when you use Hash File Online:

• ✓ Files stay local: your files are read by your browser and never transmitted anywhere. Their names, contents and hash values are not stored or logged.
• ✓ No account: use the tool immediately without registration or sign-up.
• ✓ Analytics and advertising: the site uses Google Analytics and loads Google AdSense, which use cookies. In the EEA, UK and Switzerland they wait for your consent, and you can change your choice at any time. Usage events record only things like the algorithm and number of files, never file data.

The full details are in the privacy policy.

• • Six hash algorithms: MD5, SHA-1, SHA-256, SHA-384, SHA-512 and BLAKE2b, plus MD5 + SHA-256 in one pass
• • Batch and folder hashing: hash many files, or a whole folder or pen drive, keeping each file's path
• • Verify and compare: check a file against an expected hash, or two files against each other
• • Reports: PDF, CSV, JSON, HTML or plain text, with optional case reference, source device, place and a signature block for evidence use
• • No size limit: streamed hashing handles files of any size
• • Works offline: once the page has loaded, hashing needs no connection

The tool is free and will stay free. Hosting and development are paid for by advertising (Google AdSense) and by visitors who choose to buy me a coffee. Ads never have access to your files: they run in the page like any other website's ads, while hashing happens locally on data that is never transmitted.

Found a bug, or want an algorithm or feature that is missing? Tell me through the contact page.