Cryptography & Security
Intermediate
Key Space Size
Number of possible keys for a b-bit key.
Formula
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MembersVariables
KNumber of keys
bKey length (bits)
Example
128-bit key: K = 2^128 ≈ 3.4×10³⁸
Did You Know?
AES-128 has more possible keys than there are atoms in a million Earths — brute force is hopeless.
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