Why is my battery draining so fast?

[AC Question]

My galaxy s3 battery drains super fast. It will get down to 40% battery power left and then shut off. When I go to plug it in to the charger and turn it back on, it will say it is at 70%.

 

[B. Diddy]

Welcome to Android Central! Can you try a new or different battery?

 

[christiano9911]

I think your battery is very old. You need to replace it with a new one or maybe you can try this app named "Battery Callibrator" on play store.
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