- What is a hash function?
- A hash function takes an input (like a piece of text or a file) and produces a fixed-size output called a hash digest. The same input always produces the same output, but changing even one character in the input produces a completely different hash. Cryptographic hash functions are designed so it's computationally infeasible to reverse the process or find two inputs that produce the same output.
- Is this hash generator free?
- Yes, completely free with no usage limits. All hashing runs directly in your browser — no account required.
- Is my data safe?
- All hashing runs entirely in your browser using JavaScript. No data is ever transmitted to a server or stored anywhere outside your browser. Your content stays completely private.
- What is the difference between MD5 and SHA-256?
- MD5 produces a 128-bit hash and is considered cryptographically broken — attackers can generate collisions with practical computational effort. SHA-256 produces a 256-bit hash and is considered secure for general-purpose use. For security-sensitive applications (password storage, digital signatures, certificates), always use SHA-256 or stronger.
- What is HMAC?
- HMAC (Hash-based Message Authentication Code) combines a hash function with a secret key to produce a message authentication code. It is used to verify both the integrity and authenticity of a message. HMAC-SHA256 is commonly used for API authentication, JWT signatures, and webhook verification.
- What is SHA-3?
- SHA-3 (Secure Hash Algorithm 3) is a family of hash functions standardized by NIST in 2015. Unlike SHA-1 and SHA-2 which use the Merkle-Damgård construction, SHA-3 is based on the Keccak sponge construction, giving it different structural properties. SHA-3-256 and SHA-3-512 are the most commonly used variants.
- What is BLAKE2?
- BLAKE2 is a modern cryptographic hash function designed as a faster and more secure alternative to MD5 and SHA-2. BLAKE2b (optimized for 64-bit platforms) produces 256-bit or 512-bit digests. It is widely used in modern cryptographic applications including WireGuard, IPFS, and Argon2.
- How do I verify a file's hash?
- Upload your file using the upload button in the input panel. The tool will compute the hash automatically. Then switch to Verify mode, paste the expected hash (from the software download page or checksums file), and click Verify to confirm whether the hashes match.
- Why are MD5 and SHA-1 considered insecure?
- MD5 has known practical collision attacks — meaning two different inputs can be crafted to produce the same MD5 hash. SHA-1 has theoretical and practical collision attacks demonstrated in 2017 (SHAttered). Neither should be used in new security-critical applications. For integrity checking of non-sensitive data (file deduplication, checksums), they remain acceptable.
- Can I use this for password hashing?
- No. General-purpose hash functions (SHA-256, SHA-3, BLAKE2) are designed to be fast, which makes them unsuitable for storing passwords. For password storage, use a dedicated password hashing function like bcrypt, Argon2, or scrypt, which are designed to be deliberately slow and memory-hard to resist brute-force attacks.
- Does it work offline?
- Yes. All hashing logic is bundled with the page as pure JavaScript. Once the page has loaded, the Hash Generator works without an internet connection.
