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Security

SHA-256 & SHA-512 hash calculator — verify file checksums

Generate a SHA-256 or SHA-512 hash from text or a file and compare an expected checksum. Free, private and processed locally in your browser.

● Your files stay yours

Loading converter…

Spaces and line breaks matter. Empty text is valid. For the exact bytes of a text file, use File mode.

Choose your input and select Calculate hash.

Paste only the 64-character SHA-256 or 128-character SHA-512 hexadecimal digest. Uppercase and outer whitespace are accepted; filenames and checksum lists are not.

A match only compares bytes with the supplied digest. Obtain it from a trusted source. This is not a malware scan or digital-signature verification.

How to use this tool

Choose Text or File and the hash algorithm. Enter text or select one file, then calculate. Paste the expected hexadecimal checksum to compare it without recalculating. Copy hash copies only the digest.

Good to know

Files up to 20 MiB (20,971,520 bytes); text up to 1,000,000 UTF-16 code units. Files are read into memory, never uploaded. Text uses UTF-8 without a byte-order mark, preserves spaces and uses browser textarea line endings (LF). Empty text and empty files have valid hashes. Requires Web Crypto over HTTPS. No MD5, SHA-1, HMAC or password hashing.

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Hash and checksum questions

How do I check a file’s SHA-256?

Select File, choose your file and SHA-256, then calculate. Paste the publisher’s expected hash. A matching checksum can help detect download corruption, but its authenticity depends on the source of the expected hash.

Does renaming a file change its checksum?

No. The calculation uses file contents, not its name or filesystem dates. Editing embedded metadata changes the file bytes and therefore normally changes its hash.

Why does my text hash differ from a file hash?

Encoding, a byte-order mark, trailing spaces and CRLF versus LF line endings can change the bytes. Text mode encodes the textarea as UTF-8 with LF line endings; File mode reads the original bytes.

Can I decrypt a SHA-256 hash?

Hashing is not encryption and there is no decryption key. A hash cannot be used to recover an arbitrary original file or text.

Can I use this to store passwords?

No. General-purpose SHA-256 and SHA-512 hashes are not password-storage schemes. This utility calculates checksums and does not add salts, key stretching or authentication.