File to Keccak-512.

Keccak-512 is the largest output of the original Keccak sponge from the 2012 SHA-3 competition: 512 bits from a 1024-bit capacity, 256-bit security. It is SHA3-512 before NIST's padding change, so the digests differ.

Keccak is a sponge: a 1600-bit state absorbs the input in blocks, applying a 24-round permutation after each, then the digest is read from the first bits of the state. The capacity, the part of the state never output, is twice the digest size, and that is the security margin. No length-extension attack exists against it.

Yes, with the widest margin in the family and no known attack. It is also the slowest per byte, absorbing 72 bytes per permutation. Some cryptocurrencies and pre-2015 systems use it; for new work, SHA3-512 is the standard form.

Only in the padding. NIST appended two bits to the message before the Keccak padding when it standardised SHA-3 in 2015, so SHA-3 digests differ from the original Keccak's for every input. Ethereum adopted Keccak-256 before the change and kept it, so what Solidity calls sha3 or keccak256 does not match SHA3-256. This tool gives you both families; pick the one the other side uses.

Nothing leaves your browser. The file is read on your machine and hashed there, by the browser's Web Crypto API or a WebAssembly build of Keccak-512 loaded on first use; the page makes no request with its bytes. You can load the page, go offline and keep hashing.

Drop the file onto the pane or choose it with the button. It is read into memory and hashed at once, with no size steps and no upload progress because there is no upload. Files up to 1 GB work; a 100 MB file takes well under a second on Keccak-512.

Paste the digest the publisher gave you into the Verify field, in hex of either case, with or without spaces, colons or a 0x prefix, or in Base64. The tool says whether it matches the file you dropped. A match means the bytes are exactly the ones that were published.

Hex by default, 128 characters; Base64 and Base64url are one click away and re-encode the same 64 bytes. The download button saves a line in the `digest filename` form that sha256sum-style tools read.

Yes: turn on HMAC and enter the secret, and the file is signed with HMAC-Keccak-512 rather than hashed, the same construction a server uses to sign an upload or a webhook payload.

No. The "File to Keccak-512" tool is free and opens without a sign-in, an account or an install.

Nothing. The "File to Keccak-512" tool holds your input in the page's memory, so closing or reloading the tab clears it, and it saves nothing in this browser.

The toolbar switches to Keccak-224, Keccak-256, and Keccak-384 without leaving the page. Each one reads the same input, so you can compare digests side by side.

Keccak-512 is computed by a WebAssembly build from the hash-wasm library, which the page loads the first time you hash something and reuses after that.

Yes: the Keccak-512 hash generator page has the same algorithms and options and opens on the text box. This page opens on the file pane.

Not on its own. Keccak-512 is built to be fast, and fast hashes are cheap for an attacker to guess against. Passwords need a salted, deliberately slow hash: use Argon2id, Argon2d, and bcrypt from the hash generators, which draw a fresh random salt each time.

Closest to the "File to Keccak-512" tool: Keccak-512 hash generator, SHA3-512 hash generator, Keccak-256 hash generator, SHA-512 hash generator. Each opens on its own page, free and in the browser.

The "File to Keccak-512" tool is one of 64 in its group. The group's page, /tools/hash, lists them all.

The tool is free. Its interface is built from shadcn.io's own components (Button, Input, Slider and the rest of the registry under /ui), which come in React, Vue, Svelte and Solid. Pro adds the blocks and templates for the product around it.