How to understand Kryo CPU numbering in Qualcomm Snapdragon processors

Qualcomm has a wide range of Snapdragon processors, divided into a set of series. The 8 series, for flagship processors; the 7 series, for premium mainstream; the 6 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

Kryo

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.

Kryo 2xx

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.

Kryo 3xx

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.

Kryo 4xx

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.

Kryo 5xx

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.

Kryo 6xx

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 and the Snapdragon 888+, use 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 888/888+ have three; and the Cortex-A55, of which there are 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 in the Snapdragon 8 Gen 1

When Qualcomm launched the successor to the Snapdragon 888+, the San Diego chip giant changed its processor branding significantly. The new chip follows a new naming scheme. Gone are the three-digit names in the 800 series (855, 865, 888, and so on), now we have the 8 series, with the first chip known as the Snapdragon 8 Gen 1.

The CPU setup in the Snapdragon 8 Gen 1 follows the traditions of its forebearers. It is a 1+ 3+4 setup using the latest CPU cores from Arm. The Cortex-X1 is upgraded to the Cortex-X2, the Cortex-A78 is replaced by the new Armv9 Cortex-A710, and likewise, the Cortex-A55 is replaced by the Cortex-A510.

As part of the new naming schemes, Qualcomm will no longer name the Kryo CPUs individually, the CPU setup in the Snapdragon 8 Gen 1 is simply known as the Kryo CPU. To distinguish it from other Kryo CPUs, it is the Kryo CPU in the Snapdragon 8 Gen 1.

Kryo CPU numbering cheat sheet

Before the Snapdragon 8 Gen 1, the Kryo numbering looked something 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

However, that has now all changed, the CPU is just known as Kryo and it is the processor name that helps define the actual CPU configuration. This new trend will slowly be applied to all Snapdragon processors. For example, the Snapdragon 8cx Gen 3 Compute Platform (laptop processor to me and you) also uses the generic Kryo CPU naming. In case you think the CPU is being unfairly treated, don’t worry, Qualcomm is also applying the new branding to the GPU. The GPU in the 8cx Gen 3 is known as the “Qualcomm Adreno GPU, Snapdragon 8cx Gen 3”.