My iPhone battery isn't showing the percentage of battery?

I did a hard reset on my iPhone and now the battery icon in the top right is there but the percentage that is usually next to it is now gone. I'd like to know how this happened and if I can fix it.

If you have your phone updated to ios 6 at the minimum you can turn your battery percentage on and off by going to settings>general>usage>battery usage… Its close to the bottom of the page

  • Why does the last percentage of my iphone battery takes so long to charge? I have noticed that the very first percentages (1-20) of the iphone battery charges very quickly, but when it comes to the last percentage (99-100) it takes like 15 minutes to charge!
  • What to do if your iPhone 4S battery percentage is stuck and won't change? My iphone battery percentage is stuck at 100% and I don't know what to do. The only time my battery percentage changes is if I turn my phone off and back on and it'll be on the real battery percentage but it'll still be stuck. Can someone help me with this problem?
  • Why iphone is not showing accurate battery percentage? When i slept tonight it was 60 percent, i got up in morning its still 60 percent, i plugged in charger, suddenly it became 63 percent, why? Please tell if i discharge it completely & recharge to 100 percent wil it help to calibrate? Or factory restore is must to calibrate? Please you know factory reset means all my apps will be deleted, what to do?
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