The same password takes minutes or millennia depending on who is guessing — ten tries a second at a login form against 10¹² a second on a leaked fast hash.
Those two rates are eleven orders of magnitude apart, so any single crack-time figure quoted without an attacker attached is meaningless. It also means the site operator’s choice of hash matters more than yours: moving from unsalted SHA-256 to bcrypt costs an attacker about eight orders of magnitude, which is roughly 27 bits of entropy handed to every user at once.
Guessing may not be the attack at all. Past about 80 bits nobody is brute-forcing you, and the realistic threats — phishing, malware, credential stuffing from a breach elsewhere — are completely indifferent to entropy. More bits stop being the answer long before most people stop adding them.
Estimate with the rule, then check it against the calculator that models it properly.
Open Password Strength & Crack Time →The same password takes minutes or millennia depending on who is guessing — ten tries a second at a login form against 10¹² a second on a leaked fast hash. Those two rates are eleven orders of magnitude apart, so any single crack-time figure quoted without an attacker attached is meaningless.