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SHA256 vs MD5
SHA-256 is a modern cryptographic hash. MD5 remains common in legacy checks but is broken for security uses.
Table of contents
Hash basics
A hash function turns input into a fixed-length digest. The same input should produce the same output, while a small input change should produce a very different digest. This makes hashes useful for integrity checks and fingerprints.
Hashes are not encryption. You do not decrypt a hash. You compare a newly computed digest with an expected digest.
Where MD5 fits
MD5 is fast and widely implemented, but it is no longer safe for cryptographic trust. Attackers can create collisions, meaning two different inputs with the same digest. That breaks use cases that rely on collision resistance.
MD5 still appears in legacy APIs, old file checks, and compatibility systems. It is acceptable to inspect or reproduce a legacy MD5 value, but not to design new security around it.
Where SHA-256 fits
SHA-256 is part of the SHA-2 family and is widely used for modern integrity checks, signatures, blockchain systems, package verification, and content fingerprints. It is much stronger than MD5 for collision resistance.
SHA-256 alone is still not a password storage strategy. Passwords need slow, salted, purpose-built hashing algorithms that resist brute force better than fast general-purpose hashes.
Choosing the right hash
Use SHA-256 for modern checksums and fingerprints unless a system requires another algorithm. Use MD5 only when maintaining compatibility with an existing integration that demands it.
Normalize the exact input before comparing hashes. Differences in whitespace, line endings, encoding, or hidden characters produce different digests.
Related guides
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What is a UUID
UUIDs are standardized identifiers that can be generated independently with a very low chance of collision.
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HTTP status codes quickly tell you whether a request succeeded, redirected, failed client-side, or failed server-side.
FAQ
Is MD5 secure?
No. MD5 has known collision weaknesses and should not be used for security-sensitive purposes.
Is SHA-256 reversible?
No. SHA-256 is a one-way hash, but weak inputs can still be guessed.
Can hashes store passwords safely?
Use password hashing algorithms such as Argon2, bcrypt, or scrypt instead of plain SHA-256 or MD5.
Why is MD5 still seen?
Legacy systems, old checksums, and compatibility workflows still expose MD5.