Password Strength
Rate password strength, analyse the character mix, and estimate cracking time
输入密码进行评估
弱
—
极强
强度评分：0/100
熵值：0 bits
字符组成分析
✗ 包含小写字母
✗ 包含大写字母
✗ 包含数字
✗ 包含特殊字符
✗ 长度 ≥ 12 位
✗ 非常见弱密码
破解时间估算
输入密码后显示破解时间...
安全知识
熵值 (Entropy)：衡量密码不可预测性的指标
公式：Entropy = 长度 × log₂(字符集大小)
• 纯小写：26 种字符
• 大小写+数字：62 种字符
• 大小写+数字+特殊：94 种字符
安全建议
• 至少 12 位长度
• 混合大小写、数字、特殊字符
• 避免使用个人信息（生日、姓名）
• 不同网站使用不同密码
• 定期更换重要账号密码
About this tool
The password strength checker tests whether a password is safe:
- Live score: weak, medium, strong or very strong as you type
- Composition: see which character classes the password uses
- Entropy: calculate the information entropy of the password
- Cracking time: estimates for different brute-force speeds
- Suggestions: specific ways to strengthen the current password
- Local only: the password never leaves the browser
When to use it
- Checking a new password before using it
- Auditing whether existing passwords are strong enough
- Learning what makes a password safe
- Raising the protection level on an account
Password notes
- Entropy: log2 of the character set size raised to the password length; higher is safer
- Character sets: 10 digits, 26 lowercase, 26 uppercase and about 32 symbols, roughly 94 in total
- Cracking speed: a CPU manages about one billion guesses per second, a GPU about one hundred billion
- Advice: at least 12 characters mixing case, digits and symbols