File Hash & Checksum

A checksum (or hash) is a short fingerprint calculated from a file's exact contents. The same file always produces the same hash, but change a single byte and the hash becomes completely different. That makes hashes the standard way to answer one question: "is the file I have exactly the file I was supposed to get?"

Software publishers, Linux distributions, firmware vendors and backup services publish a hash next to their download links. After downloading, you calculate the hash of your copy and compare. If they match, the file arrived intact and untampered. If they don't, delete it and download again from the official source.

Always match the algorithm the publisher used — it says so next to the download link. SHA-256 is the modern standard and the most common today. SHA-512 and SHA-384 are longer variants used when extra assurance is wanted. SHA-1 and MD5 are older; they're still published widely for software, firmware and backups, and they're fine for catching accidental corruption.

For security-critical checks — verifying that a file wasn't deliberately tampered with — prefer SHA-256 or stronger when the publisher offers it, because MD5 and SHA-1 have known weaknesses against deliberate forgery. Paste the published hash into the comparison box and the tool tells you instantly whether it matches.

Hashing only reads your file — it never modifies it, and the result is just text you can copy. Even large files hash quickly because the calculation is simple for modern devices, but the whole file is read into memory, so multi-gigabyte files work best on a desktop browser.

A matching hash proves the file is identical to the one the publisher hashed — it doesn't prove the publisher's file itself is safe. Always download from the official site, and treat a hash published on the same page as the download as a check against corruption and mix-ups, not as a guarantee against a compromised website.

Most online converters upload your file to a server, process it there and send it back. all in tool works differently: the processing code is downloaded to your browser and runs on your own device. Your file is read from your disk into memory, transformed, and handed back to you as a download. It is never sent over the network, so there is nothing for us — or anyone else — to store, read or leak.

You can confirm this yourself: once the page has loaded, you can disconnect from the internet and the tool keeps working. This also means speed depends on your device rather than your connection, which is usually much faster for large files.