The "How Secure Is My Password" tool offered by security.org is widely used and considered safe and reliable for most people to test their password strength. It checks passwords against a database of common weak passwords and assesses factors like password length, complexity, and uniqueness to estimate how long it would take a computer to crack it. The site reports that your password entries are not stored or shared, operating entirely on your device for privacy.

For best security, passwords should:

• Not contain personal information
• Avoid common phrases or consecutive characters
• Be at least 12–16 characters, ideally combining letters, numbers, and symbols

• Be unique for every account

The security community generally trusts security.org’s tool for its non- storage policy and clear privacy communication. However, as with all password tools, avoid entering your actual passwords unless you fully trust the website; consider using password variations if you're still uncertain.

In sum, security.org’s tool is a legitimate and secure option for password strength checking, and it does not send your input over the internet. For peace of mind, create long, random passwords and use a reputable password manager.