About this tool
Drop in a file to compute its MD5, SHA-1, SHA-256 and SHA-512 digests, then paste the checksum the publisher gave you to confirm they match. Pasted values are accepted in whatever form you copied them — a bare hash, a line of sha256sum output, or the BSD "SHA256 (file) = …" format — and the algorithm is inferred from the length.
This is the part that matters: verifying a download on most online checksum sites means uploading the file to them first, which is absurd for something you are checking precisely because you do not fully trust it. Here the file is read locally, hashed in a Web Worker so the page stays responsive, and never sent anywhere. Large files are read in chunks with a progress readout and can be cancelled.