Which Pi Do I Have? Includes Pi 4

With the introduction of the Pi4 board featuring multiple memory options, it's very useful to be able to identify exactly which model of Pi board you have. Here are two methods to identify your Pi:

1. Use the revision code, which provides the model, revision, RAM, and manufacturer. This applies to all models.
2. For Pi 4 boards, use the memory codes below to identify which memory variant you have visually.

Accessing Revision Codes

Each distinct Raspberry Pi model revision has a unique revision code. You can look up a Raspberry Pi's revision code by running:

cat /proc/cpuinfo

The last three lines show the hardware type, the revision code, and the Pi's unique serial number. For example:

Hardware    : BCM2835 
Revision    : a02082 
Serial      : 00000000765fc593

Note: With the previous kernel 4.9 (this is fixed in kernel 5.4), all Pis report  BCM2835, even those with BCM2836, BCM2837 and BCM2711 processors. You should not use this string to detect the processor on the older kernel 4.9.

 Here is a list of current 'new style' revision codes. For revision codes not listed here, see the full list at Raspberry Pi.org.

Pi 4 Memory Module Markings

Additionally, for Pi 4 boards that cannot be powered on, the memory module is labelled as follows:

Source: Raspberry Pi revision codes
Source: In-house information