Check how strong your password is — get an instant score, strength rating and specific tips to make it stronger.
Also generate a strong password with the Password Generator or encode data with the Base64 Encoder.
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This password strength checker works as a password security tester, password entropy calculator, and password audit tool for anyone who wants to verify that their passwords meet modern security standards before using them for important accounts.
A strong password combines four key properties: length, character variety, randomness, and avoidance of predictable patterns. Length is the single most important factor — each additional character exponentially increases the number of possible combinations an attacker must try in a brute-force attack. A 12-character password using only lowercase letters has 26¹² possible combinations, but adding uppercase letters, numbers, and symbols expands the character set to over 90 characters, making the same 12-character length vastly more resistant to attack. For truly sensitive accounts — banking, email, password managers — 16 or more characters is recommended.
Entropy is the mathematical measure of password randomness, expressed in bits. It is calculated from the password length and the size of the character set used. A password with 70 bits of entropy would require, on average, 2⁷⁰ attempts to crack by brute force — a number so large that even the fastest computers would take an impractically long time. Passwords based on dictionary words, keyboard walks (qwerty, 12345), or simple substitutions (p@ssw0rd) have far lower effective entropy than their length suggests, because attackers use wordlists and pattern rules that dramatically reduce the search space. This tool flags these weaknesses specifically so you can address them.
The most secure approach to password management is to use a dedicated password manager that generates and stores unique high-entropy passwords for every account. This eliminates the need to remember passwords while ensuring each account has a distinct, randomly generated credential. If one account is compromised in a data breach, the others remain safe. For accounts where you must remember the password — such as the password manager master password itself — a long passphrase of four or more random words is both memorable and highly secure, often exceeding 70 bits of entropy.