Check if a password appears in known breach data using a privacy-preserving hash prefix lookup. Your plaintext password is never sent to the server. Designed specifically for developers and professionals, this free online validator runs entirely in your browser to process tasks quickly and securely. Enjoy unlimited usage with no data tracking, no registration required, and an entirely ad-free experience.
Check a password to see breach results
Plaintext stays in your browser during the lookup
Check whether a password appears in known breach data using a k-anonymity hash prefix lookup.
The plaintext password stays in your browser. The range API receives only the first 5 characters of the SHA-1 hash and returns matching suffixes for local comparison.
DevToolLab is 100% free & ad-free. If this validator saved you some time today, please consider supporting our work.
Test and validate API keys for OpenAI, Anthropic, Google AI, and other services. Secure validation without storing keys on our servers.
Test regular expressions with real-time validation, match highlighting, and detailed explanations. Debug regex patterns quickly and efficiently.
Analyze password strength and security in real-time. Get detailed feedback on complexity, entropy, estimated crack time, and suggestions for improvement.