112-52 · Question #155
Which hashing algorithm produces a 128-bit hash value?
The correct answer is C. MD5. MD5 (Message Digest 5) produces a 128-bit (16-byte) hash value, making it the correct answer. SHA-1 produces a 160-bit hash, while SHA-256 produces a 256-bit hash - both are part of the SHA (Secure Hash Algorithm) family and output larger digests than MD5. AES is not a hashing al
Question
Which hashing algorithm produces a 128-bit hash value?
Options
- ASHA-256
- BSHA-1
- CMD5
- DAES
How the community answered
(37 responses)- B3% (1)
- C89% (33)
- D8% (3)
Explanation
MD5 (Message Digest 5) produces a 128-bit (16-byte) hash value, making it the correct answer. SHA-1 produces a 160-bit hash, while SHA-256 produces a 256-bit hash - both are part of the SHA (Secure Hash Algorithm) family and output larger digests than MD5. AES is not a hashing algorithm at all; it's a symmetric encryption cipher, so it doesn't produce a hash value. Memory tip: MD5 → think "MD = Mini Digest" - it's the smallest of the common hash outputs listed, and 128 bits = 32 hex characters, which you may recognize from MD5 checksums on download pages.
Topics
Community Discussion
8
Dervla O.Dec 14, 2025MD5 is your answer, C. It outputs a fixed 128-bit digest regardless of input size, which is the defining characteristic the stem is testing. SHA-1 gives you 160 bits, SHA-256 gives you 256 bits, and AES is a symmetric encryption algorithm, not a hash function at all, so D is a trap for anyone who confuses encryption with hashing. When you see a question asking about output size, pair the algorithm to its bit length and that choice collapses fast.
Anjali D.Dec 14, 2025Solid breakdown, though it is worth flagging that MD5's fixed output size is actually the least interesting thing about it for exam purposes, since all four common hash functions share that fixed-output property, so the real differentiator the question is testing is just memorizing which bit length maps to which algorithm.
Hiroshi T.Nov 23, 2025The correct answer is C, MD5. MD5, defined in RFC 1321, produces a fixed 128-bit (16-byte) digest regardless of input size, which is exactly what the question is testing. SHA-1 outputs 160 bits, SHA-256 outputs 256 bits, and AES is a symmetric encryption algorithm, not a hash function at all. If you see "128-bit hash" on the exam, the answer is MD5, full stop.
Arvydas C.Nov 15, 2025MD5 gives you 128 bits, I flagged it instantly when I saw AES listed as a distractor.
Anjali D.Dec 3, 2025MD5 gives you 128 bits, though calling AES a "hash" is the real trap here.
Grace U.Nov 8, 2025MD5 gives you that 128-bit output, though AES being in there is a fun trap since it encrypts, not hashes.
Oluwafemi F.Dec 4, 2025MD5 outputs 128 bits, caught that one instantly, almost flagged it as a trick.
Anjali D.Dec 5, 2025Good catch on the 128 bits, Femi, and worth noting for the group that even though MD5 gives you that 128-bit digest, most certs will push you to also know why it is deprecated for security use, since collision vulnerabilities are a common distractor answer in the crypto questions.