Question 1

What is a hash?

Accepted Answer

A hash (or hash function) converts input data of any length into a fixed-length output value. Common hash algorithms include MD5 (128-bit), SHA-1 (160-bit), SHA-256 (256-bit), and SHA-512 (512-bit). Hashes are commonly used for data integrity verification, password storage, and digital signatures.

Question 2

What is the difference between MD5 and SHA-256?

Accepted Answer

MD5 produces a 128-bit (32 hex character) hash, while SHA-256 produces a 256-bit (64 hex character) hash. SHA-256 is more secure with no known collision attacks. While MD5 is faster, it has known security vulnerabilities and should not be used for security-sensitive applications.

Question 3

Can a hash be reversed (decrypted)?

Accepted Answer

Hashing is a one-way function that is theoretically irreversible. While rainbow tables or brute force can be used to guess the original input, secure algorithms like SHA-256 make this computationally infeasible in practice. This is why hashes are widely used for password storage.

Question 4

Why should I verify file hashes after downloading?

Accepted Answer

Files may become corrupted or tampered with during download. By comparing the hash of the downloaded file with the official hash, you can verify the file is complete and unmodified. If the hashes match, the file is intact and trustworthy.

Hash Generator

File Hash Verification

Hash Generator

File Hash Verification

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