Chosen Solution

My laptop has been running fine, but recently when I have been using it off the charger my battery life drains much faster than usual. I have had no problems whatsoever when the laptop is plugged in, so I am thinking it could be the battery? If it is the battery do I need to replace it?

Even though it seems like your charger is properly working it is good to make sure. Another way to make sure it is not your charger is to remove your battery out of the computer and leave it on the charger. If it is working then your charger is good. The next step would be to replace your battery.