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macrumors newbie
Original poster
Jun 24, 2018
Hi All, first time poster here and 1y owner of a MacBook 12" (2017).

I came to these forums a while back looking for some documented battery benchmarks for the MacBook 12 (2017) and couldn't really find anything that I could replicate myself for comparison sake.

Yesterday I finally decided to run my own web video test and thought I'd share my system info, test environment and results for anyone curious or concerned about their MacBook 12" battery life.

System Info:

MacBook 12" 2017 i5 8gb 512gb
Battery Condition 94%
Battery Cycles: 56
High Sierra 10.13.4
Safari 11.1

Test Description:

Using Safari I played the following 10 hour YouTube Video in HD (Fullscreen) over Wifi until complete battery depletion.

Test Environment:

75% Brightness (12 bars)
Brightness Auto Adjustment (Disabled)
Sleep (Disabled)
Power Nap (Disabled)
0% Backlight
0% Sound
Notifications Disabled
Bluetooth Disabled
Startup Items Disabled (hold shift key during login)


9 hours 40 minutes
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Reactions: gitresethard

Mike Boreham

macrumors 68040
Aug 10, 2006
Thanks...good result! IME brightness setting is the dominant setting and differences in this is the main the reason why some people are happy with battery life and some not.


macrumors newbie
Oct 11, 2016
Im at 89 cycles and battery condition is down to 86%. Something wrong?


macrumors member
Aug 27, 2017
I have had it for more than a year on every day heavy use for work (about 9 hours a day min). Battery still lasts pretty well. I only have to charge it once or twice when I'm down to 70-60%. Never let it deplete or go below 50%.

I don't count cycles nor health %, I just see how long it lasts for my every day tasks.
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