Free Password Strength Checker
The Password Strength Checker estimates how strong a password is using entropy and common criteria. It runs entirely in your browser — your password is never sent anywhere.
If the score comes back weak, generate a replacement with the Password Generator and re-test it here. To find out what an unfamiliar digest was protecting, try the Hash Identifier.
How to use the Password Strength
- 1 Type the password you want to check.
- 2 Read the score, which is built from length, character variety and how common the pattern is.
- 3 Look at the specific warnings rather than the score alone — they tell you what to change.
- 4 Adjust and re-check until the warnings clear.
How to Use
Type a password to see its estimated strength and which criteria it meets. The checklist updates live as you type.
- Live entropy estimate (bits)
- Criteria checklist (length, case, numbers, symbols)
- Runs locally — nothing is uploaded
Frequently asked questions
Is my password sent anywhere?
No. The check runs entirely in your browser, so the password never leaves your device and is never stored or logged. That matters here more than almost anywhere else, which is why this tool has no network calls at all.
Why does a short password with symbols still score badly?
Because length matters far more than character variety. Adding a symbol to an eight-character password multiplies the search space by a few dozen; adding four characters multiplies it by millions. Attackers use dictionaries and pattern rules that defeat "P@ssw0rd"-style substitutions almost immediately.
What is the best way to make a strong password?
Length first, then unpredictability. A four-word passphrase from a large word list is both strong and memorable, and a long random string from the generator is stronger still. What you should avoid is reusing one password across sites — a single breach then exposes every account.
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