From wisebrother.com:
Are your passwords secure? A cyber security firm crunched some numbers and figured out how long it would take a hacker to crack ANY password.
In general, there are four things that affect how secure your password is: How long is it? Are the letters lowercase AND uppercase? Are there numbers too? And are there special characters, like an exclamation point? Here's what they found . . .
1. ANY password that's six characters or less can be cracked INSTANTLY now.
2. If your password is all lowercase letters, anything less than nine letters long can also be cracked immediately. Passwords like that don't get fairly secure until 14 letters long. And only using numbers is even worse, so don't do that.
3. If you use lower AND uppercase letters, it still needs to be 12 characters long to be somewhat secure. Ten characters can be cracked in three days . . . at 11, it's five months . . . and at 12, it would take 24 YEARS to crack. Even if you add numbers and special characters to that, it still needs to be at least 11 characters long.
So what does a password need to look like to REALLY be safe? Well, it gets exponentially more secure as it gets longer. For example, a password with 18 characters . . . including all the stuff we mentioned . . . would take 438 TRILLION years to crack.