How fast are the iPhone 6s and iPhone 6s Plus compared to one another and earlier iPhone models?

Please note that the iPhone 6s and iPhone 6s Plus have both been discontinued. However, this Q&A is up-to-date and remains quite useful for anyone considering one of these models on the used market.

Apple's formal press release for the iPhone 6s and iPhone 6s Plus boasts that the devices have a new A9 processor, "Apple's third generation 64-bit chip" with a promise of "70 percent faster CPU and 90 percent faster GPU performance than the A8" processor that powers the earlier iPhone 6 and iPhone 6 Plus models.

With such a substantial -- and specific -- performance claim, it is a safe bet that the performance improvement of these models compared to their predecessors and earlier iPhone models is significant.

Compared to one another, the iPhone 6s and iPhone 6s Plus models have essentially the same components that influence performance -- the same processors, graphics processors, and the same 2 GB of RAM -- so it would be reasonable to expect them to perform more-or-less identically for most tasks.

Photo Credit: Apple, Inc. (iPhone 6s Plus, Left; iPhone 6s, Right)

Compared to earlier models, in addition to the faster processors that Apple mentions, it also is notable that 2 GB of RAM is at least twice as much RAM as any previous iPhone model -- including the iPhone 5, iPhone 5c, iPhone 5s, iPhone 6, and iPhone 6 Plus alike -- and twice as much RAM makes a substantial impact on overall performance.

Just how substantial the performance improvement of the iPhone 6s and iPhone 6s Plus is compared to earlier models requires benchmarks and real-world testing, though.

Benchmark Performance Overview

For a solid general overview of the performance differences between the iPhone 6s and iPhone 6s Plus, earlier iPhone models, and even the iPod touch and iPad lines, Everyi.com's own Ultimate iComparison makes it quick to compare side-by-side Geekbench benchmark averages for hundreds of possible performance comparisons.

The Geekbench 3.0 benchmark shows that the iPhone 6s and iPhone 6s Plus are extremely close to the same speed, but the iPhone 6s is slightly faster, perhaps because it is driving a smaller display that is a bit less taxing on the graphics processor. However, the difference is imperceptible in day-to-day use, certainly.

Compared to the iPhone 6/iPhone 6 Plus introduced a year earlier and the iPhone 5s released two years earlier, the iPhone 6s/iPhone 6s Plus are roughly 56% and 78% faster, respectively. Not quite as much of a speed boost as reported by Apple, but substantial nevertheless.

It also is worth noting that the Geekbench 3.0 benchmark reports that the iPhone 6s actually is 7% faster in single core tasks and only about 4% slower in multicore tasks than the entry-level MacBook, the MacBook "Core M" 1.1 12" (Early 2015). The iPhone 6s still is 27% slower in single core tasks and 67% slower in multicore tasks than the entry-level 15" MacBook Pro, the MacBook Pro "Core i7" 2.2 15" (Mid-2015), but the mere fact that the iPhone line is approaching Intel notebook performance levels is a remarkable achievement for a mobile device.

Real-World Performance & Other Benchmark Tests

Although Geekbench 3.0 clearly demonstrates that the iPhone 6s and iPhone 6s Plus are roughly the same speed, and substantially faster than earlier iPhone models, other benchmarks and tests can be helpful for a well rounded perspective.

In real world use, Engadget reported:

The difference [between the iPhone 6s and the earlier iPhone 6] is obvious: Launching apps, firing up webpages and multitasking were all noticeably smoother on the newer iPhones. This performance gap can still vary a bit; the older iPhones would occasionally get close to 6s speed, but they never fully caught up. . . No dropped frames, no stuttering, no jankiness -- the 6s and the 6s Plus were the clear winners.

In graphics tests, ArsTechnica was impressed by the iPhone 6s graphics processor:

In the OpenGL and Metal versions of the GFXBench graphics tests, the A9's GPU is almost twice as fast as the A8. The Offscreen tests render the same scene at 1080p on all phones and isn't limited by refresh rate (this is why you see some phones, like the 6S, max out near 60 FPS) so it's the best way to compare raw GPU power. These GPUs are between 40 and 60 percent faster than the Exynos GPU in the Galaxy S6 and Note 5, the Snapdragon 810 in the OnePlus Two and other phones, and the Intel HD 5300 in the Retina MacBook. It's a fast chip.

In the most detailed testing of all, the always wonderful AnandTech hit the iPhone 6s with a number of benchmarks, including the Basemark OS II 2.0 web benchmark and found the iPhone 6s to be about 14% faster than its predecessors, concluding that the device is "pretty much at the very top of the stack" compared to all competing products.

Real-World Video Test Results

Opinions are helpful and benchmarks are a great way to quantify performance, but a video test always is useful, too, particularly for the performance "feel" in real-wold use.

This video from YouTuber The Tech Chap TV compares the real-world performance of the iPhone 6s and its iPhone 6 predecessor booting, as well as running the Asphalt 8 game, launching pre-installed apps, and more:

Unsurprisingly, the iPhone 6s performance boost is most notable running the game, but the boot time is much quicker, too. The real-world performance difference of basic productivity apps, on the other hand, is not nearly as noticeable.

Performance Summary

Ultimately, the iPhone 6s and iPhone 6s Plus are more-or-less the same speed as one another and provide a significant speed boost compared to all earlier iPhone models. Although independent benchmarks and real-world tests do not provide quite as large of a performance increase as Apple reports, the difference is substantial, nevertheless.

In fact, the iPhone 6s and iPhone 6s Plus models are so fast that they are starting to compete with notebook computers which bodes particularly well for the future of devices powered by Apple processors.

Also see: What are all the differences between the iPhone 6/iPhone 6 Plus and iPhone 6s/iPhone 6s Plus? How much better are the newer models than their predecessors?