That's "to 100%" but not enough room. In this thread where we were plotting our battery's full charge capacities I noticed than mine and a few other people's was lower than the design capacity (4600 mAH on 11" Air). I initially got 4592 then a bit lower and fellow poster GGJstudios kindly gave us some info on normal fluctuations and a link for Batter FAQs. Now it says in the FAQs that non-replaceable batteries on new Apple notebooks are already pre-calibrated but it "won't harm your battery" to calibrated it to make the readings more accurate and boy does it work! On another battery health thread someone suggested (paraphrasing) that you'd be lucky to get the exact design capacity. After zeroing the battery until the computer switched off and leaving it out of power overnight, charging it back to full this morning (standard calibration), I see this, bang on the design capacity spec: Full Charge Capacity (mAh): 4600 Health also went up to 98% (on iStat). Anyone else getting improved readings after calibration?