Qualcomm has a wide range of Snapdragon processors, divided into a set of series. The 800 series, for flagship processors; the 700 series, for premium mainstream; the 600 series for the mid-range; and so on. Each Snapdragon processor uses a different CPU and GPU combination. The CPUs use the Kryo branding and they have their own numbering scheme. Like many numbering schemes, it can be a bit confusing.
What is the difference between the Kryo 475 in the Snapdragon 765 and the Kryo 385 in the Snapdragon 845? Here is a quick explainer that should help you navigate the turbulent waters of Qualcomm’s CPU naming scheme.
Qualcomm Snapdragon Kryo CPU numbering explained
The “original” Kryo CPU debuted in the Snapdragon 820/821 in 2015. It was a complete custom CPU design from Qualcomm. It was a 64-bit quad-core CPU, compatible with the ARMv8 architecture. It maxed out at 2.2 GHz and was made using a 14nm FinFET LPP process.
By 2016, Qualcomm had signed a new deal with Arm which allowed it to use Arm designed CPUs however with two important benefits over other licensees of Arm cores. First, it could market the CPU cores under its own branding, Kryo. Second, it would have a say about the design of future CPU cores and could requests “tweaks” for its own semi-custom Kryo cores. Its first true semi-custom CPU design was the Kryo 485, found in the Snapdragon 855, but more about that in a moment. This new license agreement was branded as Built-on Cortex.
The Kryo 2xx CPUs use vanilla Arm Cortex-A73 and Arm Cortex-A53 CPU cores. They are found in the Snapdragon 835, 632, 636, 660, and 665. These are all octa-core CPUs with four Cortex-A73 cores and four Cortex-A53 cores. Depending on the exact model of processor, these CPUs are built using 10, 11 or 14nm FinFET LPP. Each of the Snapdragon processors that include the Kryo 2xx CPU, use it in slightly different configurations. For example, the Snapdragon 665 uses the Kryo 260, which has a max clocked speed of 2GHz and is built on 11nm. This is compared to the Kryo 280, in the Snapdragon 835, which maxes out at 2.45GHz and is built on 10nm.
The Kryo 3xx series moves from the Cortex-A73/A53 to the newer Cortex-A75 and Cortex-A55. The Kryo 360 is found in the Snapdragon 670, 710, and 712. It uses a 2+6 setup, with two Cortex-A75 cores and then six Cortex-A55 cores. The Kryo 385 is used in the flagship Snapdragon 845 and the Snapdragon 850, a Windows on Arm laptop processor. Both use four Cortex-A75 cores and four Cortex-A55 cores. The Snapdragon 845 has a max clock speed of 2.8 GHz, up from the 2.45 GHz of the Snapdragon 835.
The Kryo 4xx series was the first to truly benefit from the Built-on-Cortex partnership with Arm. While it is based on the Cortex-A76 and Cortex-A55, the A76 is a special semi-custom version supplied only to Qualcomm. The Kryo 4xx is also the most used CPU and is featured in 10 different Snapdragon processors, including the Snapdragon 855/855 Plus, the 765/765G and three laptop processors (the 8cx, the 8c, and the 7c).
The Kryo 460, Kryo 468, and Kryo 470, use the 2+6 setup (two A76 + six A55), whereas the rest all use the 4+4 setup. There is also a tweak to this variation with the Kry0 485 in the Snapdragon 855/855+, and the Kryo 475 in the Snapdragon 765/765G. The latter uses a 1+1+6 setup where one of the Cortex-A76 cores is clocked at a slightly higher frequency. It is known as the prime core. Likewise, the Kryo 485 also has a prime core with a high clock frequency and extra cache.
The Kryo 5xx series is based on the Cortex-A77. The first Qualcomm processor to use a Kryo 5xx series CPU was the Snapdragon 865 with the Kryo 585. Like the Snapdragon 855 before it, the 865 uses a prime core alongside three other high-performance cores, but all based on the Cortex-A77, with a max clock speed of 2.84 GHz. The Snapdragon 865+ is a tweaked version of the Snapdragon 865, also using the Kryo 585 but with the prime core now clocked at 3.1 GHz. The Snapdragon 870 is a tweaked, tweaked, version of the Snapdragon 865, a Snapdragon 865++ if you like. Based, like its siblings, on the Kryo 585, the prime core in the Snapdragon 870 is clocked at 3.2 GHz.
There are two types of Kryo 6xx CPUs. Those with the Cortex-X1 and those without! The Cortex-X1 is designed for high performance. As such it is larger, giving more space over to the logic and to caches. However, it is designed to be used in conjunction with other cores. While a full quad-core or octa-core Cortex-X1 based CPU is possible it is likely that any such processor would be reserved for laptops. For mobile, there is just one X1 core. The Snapdragon 888, being a flagship processor, uses the Kryo 680 and features three different types of CPU cores, one of which is the Cortex-X1. The other two types of core are the Cortex-A78, of which the Snapdragon 888 has three; and the Cortex-A55, of which the Snapdragon 888 has four. The Cortex-X1 core acts as the primary core in the same kind of 1+3+4 setup as found in the Snapdragon 855 and 865.
The Kryo 670 is a cut-down version of the Kryo 680 and doesn’t feature the Cortex-X1. Instead, there are four Cortex-A78 cores in a 1+3 setup with the prime core is clocked at 2.4 GHz; and four Cortex-A55 cores. The Kryo 670 can be found in the Snapdragon 780, an interesting processor that slightly breaks in the mould, in that it brings the latest Arm Cortex CPU designs to the Snapdragon 700 series but not in a 2+6 setup, but rather a full 4+4.
Kryo CPU numbering cheat sheet
A birds-eye view of the Kryo range looks like this:
- Kryo = Qualcomm custom
- Kryo 2 = Cortex-A73
- Kryo 3 = Cortex-A75
- Kryo 4 = Cortex-A76
- Kryo 5 = Cortex-A77
- Kryo 6 = Cortex-A78 with optional Cortex-X1
From the Kryo 3xx series onwards there is a little cheat to help remember which Cortex CPU core is used. The last digit of the Cortex core is always two more than Kryo series number. So the last digit of the Cortex CPU in the Kryo 3 series is 5 (3 + 2) and so it is the Cortex-A75. For the Kryo 6, it is 6 + 2, which means the Cortex-A78.
If this shortcut will work for the Kryo 7xx series and the next Cortex CPU core, only time will tell! For more on the subject of Kryo CPU numbering, be sure to check out the video at the top of this article.