Developer Utilities · Free tool
Password Strength Checker
Check how strong a password is — entropy bits, estimated time to crack, and what to improve. Private, offline.
Strength: —
Length
0
Entropy
0 bits
Crack @10B/s
instant
- At least 12 characters
- Contains uppercase letter
- Contains lowercase letter
- Contains digit
- Contains symbol
- No common patterns (password, 12345…)
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What it does
Check how strong a password is with a live score (0 – 4), a color bar, entropy bits, and an estimated time-to-crack at 10 billion guesses per second. A checklist flags missing criteria (length ≥ 12, uppercase, lowercase, digits, symbols, no common patterns). The tool also warns on common passwords like “password” or “123456”.
Nothing ever leaves your browser — no network calls, no logging. For generating strong passwords use password generator; to check if a password is already in a breach, password breach checker.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/password-strength-checker" width="100%" height="720" frameborder="0" loading="lazy" title="Password Strength Checker" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Type the password you want to evaluate.
- Read the strength score and entropy estimate.
- Fix any items the checklist flags red.
- Aim for “Strong” or better before using the password.
See how this compares
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Guides about this topic
- Developers & Technical · GuideHow to measure password strengthAnalyze password strength using zxcvbn scoring, length over complexity, and attack models. A free online tool for breach-aware security, no sign-up needed in seconds.
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- Using Our Tools · GuideHow to create a strong passwordGenerate a strong password instantly online for free. Build high-entropy passphrases following NIST 2026 rules with no download needed.
- Developers & Technical · GuideHow to encode and decode Base64Understand the 3-to-4 mechanic and 33% overhead for standard, URL-safe, and MIME Base64. Free online reference to avoid common mistakes, no download needed.
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- Developers & Technical · GuideHow to use JWT tokens securelyImplement secure JWT authentication by choosing RS256, setting expiration, using httpOnly cookies, and preventing 'alg: none' attacks in your browser for free.
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