File to xxHash3.

xxHash3 (XXH3) is the 2019 redesign of xxHash by Yann Collet. It keeps a 64-bit output and reaches the same memory-speed throughput on long inputs, but it was rebuilt for short keys (a few bytes to a few hundred) and for SIMD, with SSE2, AVX2, AVX-512 and NEON paths. The 128-bit variant is xxHash128.

No, and it does not try to be. xxHash is a non-cryptographic hash: it has excellent distribution and passes the SMHasher test suite, but anyone who knows the algorithm can make two inputs collide. Use it for hash tables, checksums and deduplication; use SHA-256 or BLAKE3 when an attacker might choose the input.

Different code for each length band: tiny inputs go through a few multiplies with no loop, mid-sized ones through unrolled stripes, long ones through a vectorised accumulator over 64-byte stripes with a 192-byte secret. That is why it is as fast on an 8-byte key as on a gigabyte.

The tool uses seed 0, the reference implementation's default and what xxhsum prints. A different seed gives a completely different hash, which is how a hash table can defend against crafted collisions; if a system you compare against seeds its xxHash, its values will not match these.

Anything new that needs a fast non-cryptographic hash: hash tables, bloom filters, sharding keys, change detection. It is in the Linux kernel's tooling, in several databases and in the xxhsum utility (-H3). Formats that already specify XXH32 or XXH64 keep those.

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 xxHash3 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 xxHash3.

Paste the checksum 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, 16 characters; Base64 and Base64url are one click away and re-encode the same 8 bytes. The download button saves a line in the `checksum filename` form that sha256sum-style tools read.

No. The "File to xxHash3" tool is free and opens without a sign-in, an account or an install.

Nothing. The "File to xxHash3" 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 xxHash32, xxHash64, and xxHash128 without leaving the page. Each one reads the same input, so you can compare digests side by side.

xxHash3 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.

No: xxHash3 is a checksum or fast non-cryptographic hash, and none of the algorithms in this toolbar take a key, because a keyed checksum proves nothing.

Yes: the xxHash3 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. xxHash3 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 xxHash3" tool: xxHash3 hash generator, xxHash128 hash generator, xxHash64 hash generator, BLAKE3 hash generator. Each opens on its own page, free and in the browser.

The "File to xxHash3" 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.