The new iPhones have smaller batteries than their predecessors, but Apple says you will still get similar battery life (AAPL)

Phil Schiller iPhone 8 iPhone 8 Plus

The iPhone 8 and iPhone 8 Plus have smaller capacity batteries than last year's iPhone 7 and iPhone 7 Plus, respectively.

Notorious leaker Steve Hemmerstoffer — also known as @onleaks — discovered TENAA listings that provide a closer look at the two devices' spec sheets, which confirmed the detail (TENAA is the Chinese equivalent of the US' FCC).

The iPhone 8 has a 1821mAh battery, whereas the iPhone 7 has a 1960mAh unit; the iPhone 8 Plus has a 2675mAh battery and the iPhone 7 Plus has a 2900mAh battery.

(In addition to that, the sheets confirm that the iPhone 8 has 2GB of RAM, while the iPhone 8 Plus has 3 — just like the iPhone 7 and 7 Plus.)

For those how cares about, Tenaa just confirmed #iPhone8 and #iPhone8Plus comes with 2GB and 3GB of RAM, reveals 1821mAh and 2675mAh battery http://pic.twitter.com/NnIvYkVuAk
— Steve H. (@OnLeaks) September 14, 2017

However, Apple explicitly says on its website's product page that the iPhone 8 family should last "about the same" as the 7's.

The two phones may have battery units that are physically smaller, but Apple has optimised its software to achieve improved battery life. One of the ways it does this is by fine-tuning the system-on-a-chip (SoC), in this case the A11 Bionic.

Now equipped with a custom, Apple-made GPU, the new A11 is markedly more powerful (and performant) than last year's A10 Fusion — at least according to the company — so that's the likeliest reason why the new phones can achieve similar results.

iPhone 8 battery

Our full review of both the new handsets is coming soon, so stay tuned to Business Insider to learn how the iPhone 8 and 8 Plus hold up against the previous models.

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