SHA3-256 Generator Online

SHA3-256 is a cryptographic hash function that produces a fixed-size output of 256 bits. It was standardized by NIST (National Institute of Standards and Technology) in August 2015 as a part of the SHA-3 family of hash functions, which includes SHA3-224, SHA3-384, and SHA3-512.

What is a hash function?

A hash function is a mathematical function that takes an input (message) and produces a fixed-size output (hash). The output is typically a string of characters or bits that represents the input in a unique way. Hash functions are widely used in cryptography to ensure the integrity and authenticity of data.

Hash functions have several properties that make them useful for cryptography. They are deterministic, meaning that the same input will always produce the same output. They are also one-way, meaning that it is computationally infeasible to reverse the function and recover the input from the output. Additionally, a small change in the input will produce a completely different output, which makes hash functions useful for detecting even small changes in data.

How does SHA3-256 work?

SHA3-256 works by taking an input message of any length and dividing it into blocks of 1088 bits. The message is then padded with bits to ensure that it is a multiple of 1088 bits long. The padded message is then processed in a series of rounds, each of which consists of several operations.

The operations used in SHA3-256 include:

• Theta: This operation creates a new value by XORing certain bits from each of the words in the message block.
• Rho: This operation rotates each word in the message block by a certain amount.
• Pi: This operation rearranges the words in the message block into a new order.
• Chi: This operation creates a new value by XORing certain bits from each of the words in the message block with the negation of certain bits from other words.
• Iota: This operation XORs a word with a constant value that depends on the current round.
• After the last round is completed, the resulting message block is XORed with a fixed value to produce the final hash value.

How is SHA3-256 used in cryptography?

SHA3-256 is used in a variety of cryptographic applications, including digital signatures, message authentication codes (MACs), and key derivation functions. In these applications, the hash function is used to ensure the integrity and authenticity of data.

For example, in digital signatures, the hash function is used to produce a fixed-size representation of the message that can be signed. The signature is then produced by encrypting the hash value with the signer's private key. To verify the signature, the recipient decrypts the signature using the signer's public key and compares the resulting hash value with the hash value of the received message.

In MACs, the hash function is used to produce a fixed-size representation of the message that is then combined with a secret key using a cryptographic algorithm to produce a MAC value. The MAC value can then be used to verify the integrity of the message.

In key derivation functions, the hash function is used to produce a fixed-size representation of a password or other secret value. The hash value is then used as input to a key derivation function that produces a key that can be used for encryption or decryption.