How to tell which Raspberry Pi 4 RAM size do I have?

So...which Raspberry Pi 4 RAM size do I have?

If your Raspberry Pi is already up and running, you can easily check for the memory size within the OS (Raspbian or Raspberry Pi OS) by running the followig command in terminal:

free -h

However, if your Raspberry Pi is sitting in front of you right now, you can simply look at the marking on the RAM chip. Refer to the picture below (2GB version shown):

At the time of writing, the marking code is as follows:

• 1GB - 4HBMGCJ
• 2GB - D9WHZ
• 4GB - D9WHV
• 8GB - D9ZCL

Have fun!