The early tests show about 10-12h, which is the same as my (and many other) laptops under regular usage.
Here's an early test that’s quite different from what you described. I’d bet dollars to doughnuts your laptop can't play fullscreen, 4k/60fps video for 20 hours using only the battery:
In fullscreen 4k/60 video playback, the M1 fares even better, clocking an easy 20 hours with fixed 50% brightness. On an earlier test, I left the auto-adjust on and it crossed the 24 hour mark easily. Yeah, a full day. That’s an iOS-like milestone.
Another one:
Just 17% of the battery to output an 81GB 8k render.
Here's an early test that’s quite different from what you described. I’d bet dollars to doughnuts your laptop can't play fullscreen, 4k/60fps video for 20 hours using only the battery:
In fullscreen 4k/60 video playback, the M1 fares even better, clocking an easy 20 hours with fixed 50% brightness. On an earlier test, I left the auto-adjust on and it crossed the 24 hour mark easily. Yeah, a full day. That’s an iOS-like milestone.
Another one: Just 17% of the battery to output an 81GB 8k render.
These are just a couple of highlights from the article "Yeah, Apple’s M1 MacBook Pro is powerful, but it’s the battery life that will blow you away": https://techcrunch.com/2020/11/17/yeah-apples-m1-macbook-pro...
You have to look at the totality of the what's going on.
In short, the M1 Macs are right up there with the fastest machines available at reasonable prices and at a fraction of the power consumption.
The machines set a new level of performance per watt and there's no disputing that. That's pretty good for their first attempt at Apple Silicon Macs.