Hash-generaattori

(Dokumentaatio englanniksi)

What it does

Computes four

hashhashA one-way function that maps data of any size to a fixed-length digest. Same input, same digest; any change, different digest; not reversible.

digests of your text at once - SHA-1, SHA-256, SHA-384, and SHA-512 - live as you type. Each row shows the algorithm, its hex digest, and its own copy button; Copy all takes the four name: digest lines together. The full digest always sits in the row’s tooltip, so nothing is lost to truncation. A stat line reports the algorithm count and the input size in bytes.

HashingHashingA one-way function that maps data of any size to a fixed-length digest. Same input, same digest; any change, different digest; not reversible.

runs in your browser via WebCrypto’s SubtleCrypto, which requires a secure context: https or localhost.

How to use it

1. Type or paste text into Input.
2. The four digests recompute on every keystroke.
3. Hover a row to read the full digest. Use that row’s copy button for one digest, or Copy all for the four of them.

Examples

The standard test vector abc:

Algorithm	Digest
SHA-1	a9993e364706816aba3e25717850c26c9cd0d89d
SHA-256	ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad

Stat line for this input: 4 algorithms · 3 byte input.

Change one character and every digest changes completely. SHA-256 of abd is a52d159f262b2c6ddb724a61840befc36eb30c88877a4030b65cbe86298449c9, which shares nothing readable with the abc digest above.

How

hashinghashingA one-way function that maps data of any size to a fixed-length digest. Same input, same digest; any change, different digest; not reversible.

works

A

hashhashA one-way function that maps data of any size to a fixed-length digest. Same input, same digest; any change, different digest; not reversible.

function reads an input of any size and produces a fixed-size digest. The same input always produces the same digest. Different inputs produce unrelated digests, thanks to the avalanche effect: every input bit influences every output bit, so a one-character change rewrites the whole result. The output length is a property of the algorithm, not the input:

Algorithm	Digest bytes	Hex characters
SHA-1	20	40
SHA-256	32	64
SHA-384	48	96
SHA-512	64	128

The digest itself is raw bytes. The tool prints it in hexadecimal, where one byte becomes two characters. That is why a 3-byte input still yields a 64-character SHA-256.

The four algorithms are not interchangeable. SHA-1 is collision-broken: in 2017 the SHAttered attack produced two different documents with the same SHA-1 digest, so it must not sign or verify anything. The SHA-2 family (SHA-256 and up) remains the standard, with SHA-256 the common default for

checksumschecksumsA short digest computed from a block of data, compared after transfer or storage to detect corruption. Changing one bit changes the checksum.

and signatures.

Good to know

• Not for passwords: a plain

  hashhashA one-way function that maps data of any size to a fixed-length digest. Same input, same digest; any change, different digest; not reversible.

  of a password is reversed in seconds by lookup tables. Password storage needs a slow salted construction like Argon2 or bcrypt. This tool is for inspecting and verifying digests of text, files, and downloads.
• Encoding matters: the input is hashed as UTF-8 bytes, so a character like é counts as 2 bytes in the stat line.
• Deterministic: paste the same text on any machine and you get the same four digests. That is what makes a digest usable as a fingerprint.
• Secure context required: the page must load over https or localhost, or the browser withholds SubtleCrypto.
• Related tools:

  HashHashA one-way function that maps data of any size to a fixed-length digest. Same input, same digest; any change, different digest; not reversible.

  Type Identifier,

  Base64Base64An encoding representing binary data as 64 safe ASCII characters, so it survives transport through text-only channels. It encodes — it does not encrypt.

  ,

  UUIDUUIDA 128-bit identifier generated to be practically unique without coordination, most commonly in version-4 (fully random) form.

  Generator.