It really, really, depends on your usage. If I use mine for phones calls and text messages only,I can go about a day to a day and a half with out charging it. Normal use (for me) I have to charge mine every night.
To find out what version your BlackBerry OS is:
- Click on the options icon
- Click on "about". This tells you what kind of BB you have, the version, etc.
And, welcome to the forums