File Hash Calculator

A hash is a unique digital fingerprint of a file. Even a tiny change (like one pixel or one letter) will create a completely different SHA-256 hash. This tool calculates the SHA-256 (for exact data) and pHash (for images) directly in your browser. Your file is never uploaded.

Select a file to calculate its hashes.

How This Works (And Why You Need It)

Why do I need a hash? Can't I just use the 'Date Created' on my file?
File metadata (like 'Date Created' or 'Date Modified') is unreliable and can be easily faked. A hash is different. It's a mathematical fingerprint. This hash, when recorded on the blockchain (which is what Signaturum does), creates a *permanent, unchangeable, and globally verifiable* timestamp. It's objective proof.
How does this help me in a legal dispute?
This is your 'weighty argument'. Imagine you claim you wrote a song in January. The other person claims they wrote it in February. A 'Date Created' timestamp is weak evidence. But a *blockchain certificate* from January, containing the hash of your song file, is definitive proof that your file *existed* in that exact state at that time. It's a digital notary.
What do I do with these hashes? What's the next step?
This tool just calculates the hashes. The *real* power comes from *fixing* this hash. You copy the hash (SHA-256 for most files, pHash for images) and paste it into your Signaturum dashboard to create a permanent blockchain certificate. That certificate is your proof.
What's the *real* difference? SHA-256 vs. pHash
Use this simple analogy:
SHA-256 is a 'Perfect Fingerprint'. It's for proving a file is 100% identical. Used for documents, contracts, code, and audio.
pHash is a 'Visual Fingerprint'. It's for proving an image *looks* the same. Used for photos and art. A pHash will match even if the file is resized, screenshotted, or re-saved (e.g., PNG vs JPG).
Is this the same as registering with a notary?
It serves a similar purpose (proving a file's existence at a specific time) but is faster, cheaper, and fully digital. A blockchain record is global and doesn't rely on one company's database. It is a powerful modern alternative to traditional escrow.
What is 'Verify' mode for?
This is for checking. Imagine you have a Signaturum certificate with a hash on it. You can paste that hash into the 'Verify' field, upload your file, and this tool will instantly confirm if it's the *exact* file (SHA-256) or a *visual match* (pHash) for that certificate.
Is this secure? Is my file uploaded?
Yes, it is 100% secure. Your file *never* leaves your computer. All calculations (SHA-256 and pHash) happen directly in your web browser using JavaScript. Nothing is sent to our server.