Double poll here. There are two questions: How much DATA do you have Oo-line? This is data and not total capacity. This includes all your on-line data: music, images, video, the OS, all of it. It doesn't include back-up data even if it's on-line like Time Machine tho. Just active data. And of the on-line storage devices used for that DATA totally, what % are they filled to? For example if you had two 500 GB drives and about 400 GB of data you would answer: "I have < 500 GB of DATA on-line." and, "My on-line storage is between 25% and 50% full.".