Generate a
24-character
password

Yes, for all practical purposes. Grover's algorithm can theoretically halve the effective security of symmetric encryption against quantum computers — meaning 256-bit security becomes equivalent to 128-bit. At 156 bits of entropy, even a halved effective strength (~78 bits) remains computationally infeasible under current quantum computing trajectories.

For brute-force resistance, the threshold is around 80-100 bits of entropy — which you reach at 12-16 characters of full character variety. Beyond that, you're not defending against brute force but against future hardware or algorithmic improvements. 24 characters provides a substantial safety margin.

Master passwords for password managers, SSH key passphrases, BitLocker/FileVault encryption keys, admin credentials for servers you manage, and any secret you won't rotate for years. The longer the expected lifetime of the credential, the longer the password should be.

Seamlessly — all major password managers (Bitwarden, 1Password, Dashlane, KeePass) support passwords of 24 characters and beyond. Most modern sites also support them. The only exception is legacy systems with short maximum-length caps, which should be considered a security deficiency.

Yes, but the impact is smaller than at shorter lengths. At 24 characters, length dominates the entropy calculation. That said, enabling all character types is still the best practice — it maximises entropy per character and satisfies any site's complexity requirements.