Data and files
File hash calculator
Calculate SHA-256, SHA-384 or SHA-512 without uploading your file.
Any file up to 20 MiB, including an empty file. WebCrypto processes all bytes in a cancellable Worker with a 30-second limit. The file is neither uploaded nor saved. A hash alone does not authenticate the sender or detect malware.
What this tool does
Calculate SHA-256, SHA-384 or SHA-512 from a file’s bytes and optionally compare an expected digest.
How to use it
- Select a file up to 20 MiB, including an empty file.
- Choose the algorithm and enter a trusted reference digest if available.
- Calculate and compare; references must use the same algorithm.
Verifiable example
- Input
- A file containing the three ASCII bytes abc, SHA-256.
- Expected result
- ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad
Limitations to review
- A hash is not encryption, a digital signature or an antivirus. An untrusted digest supplied with the file does not authenticate its sender.
- WebCrypto reads all bytes rather than streaming. A cancellable Worker uses a 30-second timeout. Expected digests must have the exact length.
Related tools
Browse all guides. Local processing: the page downloads HTTP resources but does not send files or input data to a server for these functions.