SHA Hash Generator

About this sha hash generator

Tool operation

Hashes text or a selected file locally with SHA-256, SHA-384, or SHA-512. This tool does not offer MD5 or SHA-1.

Worked example

Limits

The page offers SHA-256, SHA-384, and SHA-512 only; it does not provide MD5 or SHA-1. A digest proves neither file origin nor signer identity, and a user must independently compare it with a trusted expected value.

A cryptographic hash function computes a fixed-length deterministic bit string (digest) from arbitrary byte inputs. This tool leverages the browser's native hardware-accelerated Web Crypto API (SubtleCrypto.digest) to calculate SHA-256, SHA-384, and SHA-512 hexadecimal checksums for both plain text and local binary files up to 250 MB. Processing executes completely inside browser memory without network uploads.

SHA-2 family design and NIST FIPS 180-4

SHA-256, SHA-384, and SHA-512 belong to the SHA-2 family defined in NIST FIPS PUB 180-4. All three algorithms are Merkle-Damgård hash functions that process input in fixed-size blocks: SHA-256 uses 512-bit blocks with 32-bit words and produces a 256-bit (32-byte) digest, while SHA-512 uses 1024-bit blocks with 64-bit words and produces a 512-bit (64-byte) digest. SHA-384 uses SHA-512 initialization vectors but truncates the output to 384 bits, providing 192-bit security against collision attacks. The SHA-2 algorithms apply message scheduling, bitwise operations (AND, OR, XOR, rotation), and addition modulo 2^32 or 2^64 across 64 or 80 compression rounds per block.

Hash integrity verification workflow

Software distributors publish SHA-256 or SHA-512 checksums alongside download packages so users can independently verify that a downloaded file is identical to the original. The verification workflow is: download the file, obtain the expected hash from the publisher over a separate trusted channel (not the same page that served the file), compute the hash locally using a trusted tool or this browser tool, and compare the full hex string character by character. A mismatch indicates transmission corruption, storage error, or tampering. For software security verification, use the BLAKE3 algorithm where available, as its structured authentication approach is more resistant to length-extension attacks than unkeyed SHA-2. This tool leverages the browser's native hardware-accelerated Web Crypto API (SubtleCrypto.digest) to calculate SHA-256, SHA-384, and SHA-512 hexadecimal checksums for both plain text and local binary files up to 250 MB. Processing executes completely inside browser memory without network uploads.

Known SHA-256 test vector

What a matching checksum means

An exact digest match is strong evidence that the bytes you received match the bytes used to publish the expected digest. It does not identify the publisher: if an attacker can replace both a file and the checksum shown beside it, the comparison can still pass.

Security and performance limits

• Text is encoded as UTF-8 before hashing; visually similar Unicode sequences can have different bytes and hashes.
• This browser version reads a file into memory and therefore limits files to 250 MB.
• SHA digests are not encryption and cannot be reversed into the original input.
• Fast general-purpose hashes should not be used directly for password storage; use a dedicated password-hashing function with salt and appropriate cost.

NIST FIPS 180-4 Secure Hash Standard · Content owner: CZOA Tools · Review methodology

How to use it

1. Choose SHA-256, SHA-384, or SHA-512.
2. Enter text or choose a local file.
3. Read the lowercase hexadecimal digest.
4. Compare it independently with a trusted expected value when authenticity matters.