OmniCalcsPassword Strength Checker
Check how strong your password really is — with entropy, time-to-crack estimates and tips.
How to Use This Checker
Type a password and the analysis updates live. The estimate assumes an offline attacker making about 1 billion guesses per second.
- This is an estimate — real-world risk depends on many factors.
- Long passphrases (4+ random words) beat short complex strings.
Frequently Asked Questions
Is my password sent anywhere?
No. The analysis runs entirely in your browser — nothing is transmitted or stored.
What is entropy in bits?
A measure of unpredictability. 80+ bits is considered strong; 100+ is excellent. Each bit doubles the search space.
Why does a dictionary word score low?
Common words and phrases are tried first by attackers. This checker scores by character diversity and length, not word lists.
What makes a strong password?
Long (14+ chars), varied (mix of cases, digits, symbols) and unique — never reused across sites. A password manager helps.
Practical Example
Type "MyP@ssw0rd!" — 11 characters mixing upper and lower case, digits and symbols. The character pool is 26 + 26 + 10 + 33 = 95, giving an entropy of 11 x log2(95) ≈ 72 bits, which the checker labels Strong. At 1 billion guesses per second, an exhaustive search would take roughly 150,000 years.
- Longer is stronger: every extra character multiplies the search space by the pool size.
What Your Results Mean
- Entropy (bits) — a measure of unpredictability; each bit doubles the combinations an attacker must try.
- Estimated crack time — how long an offline attacker at about 1 billion guesses per second would need.
- Strength label — the Very weak to Very strong band your entropy falls into.
- Length and character pool — the two inputs that drive the score; reuse of common words is not detected.