Question 1

What is a hash function?

Accepted Answer

A hash function takes any input (text or file) and produces a fixed-length string of characters called a hash or digest. The same input always produces the same hash, and even a tiny change in input produces a completely different hash. Hash functions are one-way — you cannot reverse a hash back to the original data.

Question 2

What is the difference between MD5, SHA-1, and SHA-256?

Accepted Answer

MD5 produces a 128-bit (32 hex characters) hash and is fast but cryptographically broken — do not use for security. SHA-1 produces 160 bits (40 hex chars) and is also considered weak for security uses. SHA-256 (32 bytes, 64 hex chars) and SHA-512 (64 bytes, 128 hex chars) are part of the SHA-2 family and are currently considered secure for cryptographic purposes.

Question 3

How do I verify a file checksum?

Accepted Answer

Switch to the "File hash" tab, drop or select your downloaded file, choose the algorithm matching the checksum provided by the source (often SHA-256), compute the hash, then paste the expected checksum in the "Verify checksum" section and click Verify. If they match, the file is intact and unmodified.

Question 4

Is MD5 safe to use?

Accepted Answer

MD5 is not safe for security-sensitive uses such as password hashing or digital signatures because collisions (two different inputs with the same hash) can be generated. However, MD5 is still useful for non-security purposes like checking file integrity against accidental corruption, or as a quick checksum when security is not a concern.

Question 5

Does this tool send my data to a server?

Accepted Answer

No. All hashing is performed entirely in your browser using the Web Crypto API (for SHA algorithms) and the spark-md5 library (for MD5). Your text and files never leave your device. The tool works fully offline once the page is loaded.

Question 6

What is a salt and should I use it with this tool?

Accepted Answer

A salt is random data added to input before hashing to prevent rainbow table attacks. This tool generates standard unsalted hashes. For password storage, always use a dedicated password hashing function (bcrypt, Argon2, scrypt) — not MD5 or SHA with or without a salt.

Algorithm	Output length	Security	Common use
MD5	32 hex chars	Broken	Non-security checksums
SHA-1	40 hex chars	Weak	Legacy compatibility
SHA-256	64 hex chars	Strong	File integrity, certificates
SHA-384	96 hex chars	Strong	TLS, code signing
SHA-512	128 hex chars	Very strong	High-security applications

Hash Generator Online Free — MD5, SHA-256, SHA-512 Checksum Tool

How It Works

Hash Algorithm Comparison

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