# AES vs Blowfish taking key-length into account

I understand that Blowfish is getting old, but is still a secure algorithm, and that AES is very popular, and is recommended by most people. My question is, how do the two compare when a 256-bit key is used for AES, and a 448-bit key (the maximum according to the standard) is used for Blowfish? Would Blowfish with a 448-bit key be more resistant to brute-force attacks? Are there any other considerations? (let's assume that we already agree that 256-bit keys are sufficiently resistent to brute-forcing).

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As for strict brute force complexity, I think you've pretty much answered your own question, if we assume that 256-bit keys are sufficiently resistant to brute-forcing then using a longer key makes no sense. It's like trying to decide what's best between "infeasible" and "infeasible". But theoretically speaking, Blowfish uses all 448 bits of the key, so a brute-force attack would take on average $2^{447}$ guesses at the key, whereas AES would take $2^{255}$ guesses on average (AES-256, that is).