Air Battery

[dfeigenbaum1]

Is there a app to test battery, or hardware test, I only get 3 hours

 

[miles01110]

What would a battery utility tell you? Time remaining is highly dependent on usage. That should be completely obvious.

 

[dfeigenbaum1]

Brightness on 2, only running safari and mail, nothing else

 

[simsaladimbamba]

Coconut Battery, System Profiler > Power and iStat Pro.

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This should answer most, if not all, of your battery questions:
Apple Notebook Battery FAQ by GGJstudios
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Also have a look at Activity Monitor (Applications / Utilities /) and select All Processes and sort by CPU to see what the culprit may be.

image below uses sorting by CPU as an example

Further reading:

Mac OS X: Reading system memory usage in Activity Monitor
Making The Most of Activity Monitor​

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