Analyze password strength in real time with entropy, crack time, and character composition.
No data is sent anywhere. All analysis runs entirely in your browser.
Check password strength instantly with this free, privacy-first browser tool. See real-time feedback on character composition, entropy, and estimated crack time without any data ever leaving your device. Use it to evaluate existing passwords or test new ones before committing them to a password manager or online account.
A password strength checker analyzes a given password against multiple security criteria to determine how resistant it is to automated attacks such as brute force, dictionary attacks, and hybrid cracking techniques. Unlike online checkers that may transmit your password to a server, this tool performs all computation locally using JavaScript in your browser. It evaluates character pool diversity, length, entropy, and estimated time to crack at current hardware speeds. The result is a clear strength rating from Very Weak to Very Strong along with detailed composition statistics. Understanding password strength helps users make informed decisions about their credential security posture and encourages the adoption of longer, more complex passwords or passphrases.
Type or paste a password into the input field. The tool instantly analyzes it and displays a color-coded strength meter that moves from red (Very Weak) through orange, yellow, and green to dark green (Very Strong). Below the meter you will see exact counts for uppercase letters, lowercase letters, numbers, and symbols, along with total character count and entropy measured in bits. The estimated crack time calculation assumes a modern GPU-accelerated brute-force attack running at ten billion guesses per second. Use the show/hide toggle to reveal the password while analyzing it.