I have been thinking about running my passwords through those "how strong is your passwords" but I wonder "how safe those sites are".

Run them by me. I'm an expert.

The best way is to type it here with your username and we can judge. ;)

I wouldn't, if i were you. Try spoofing: replace letters with other letters, numbers with other numbers, symbols with other symbols. Then you don't have to worry.

On the flip side, password security is a joke. If you get compromised once, that pass is toast. Meanwhile, what we're really testing for is how "guessable" your password is. If it is a common word, acronym, or euphemism, it's guessable. Some sites make certain features of passwords mandatory (like must use numbers), which actually makes passwords using them less secure (since we know there must be a number, so the required number is usually either a "favorite number" or the number "1" or the birth year or the year the account was created. If the password must be at least a certain number of characters, you can cut down on possibilities that way, too.

That said, something like o4ta5f is something i came up with by smashing the keyboard twice and if you managed to memorize something of that format, i doubt anyone would break into it, but at the same time it would be considered "weak" and wouldn't even pass most password requirements.

The only truly safe password is one that the user doesn't know.

If you immediately know the candle has been lit, the meal was cooked a long time ago.

Great idiom, but where the hell did that come from?

But were fresh ingredients harvested from the cistern?

As a great man once said - never reveal your sources, or in this case; your passwords. ;)

Hint: search it on ddg or google. To make a long story short; once in a blue moon...

You should never share your password. If you want to test your password you can use a password manager. They usually have predefined password patterns for generating passwords, compare that to yours. Just make sure the program is well known, preferably open source.

safe is not a safe password. Better try another one.

Seriously, never use/trust a cloud based password manager. Instead, use a local one as this one:

https://www.keepassx.org/ (open source and cross-platform)

or https://keepass.info/

When you make an entry and enters the password it will tell you its strength, and it can also generate one for you based on your criteria.

EDIT: Pass-phrases between 13 and 16 char is generally good and also not totally difficult to remember (the 16 limit is because of windows, linux doesn't have that limit, strangely enough).

It's in SG-1, don't know where else...

Plus to that one. Keepass is a great little password manager. You can get it via portablapps.com as well, so easy to have on an encrypted pen drive and run on any machine without install. You only need to remember the password to the pen drive, and make sure you keep that safe then. Oh, and take a backup of your password database as well and store separately in case you do lose the pen drive.

I just downloaded the zip file of KeePass 2 off the official site and extracted to a folder on the USB drive on which I have one of the database copies, no need to bother with portableapps. With mono, the same binary runs fine on Linux and OS X (but I have the application installed on the machines I am the primary user, most of which run GNU/Linux-based systems). There are very few services I set my own passwords for, most are randomly generated by KeePass.