I am looking for the smallest LED

Hi everyone I am looking for the smallest blinking LED. I also want to find out if the smalest LED is multicolour! I have just started my journey in electronics with a Raspberry Pi workshop.
Any help is appreciated!
Thanks
Dimitrios

Do you want an led that attaches to a pcb? If so you can get some tiny 0603 size leds.

If you want a discrete led to attach to the raspberry pi header, then a T3 (3mm diameter) would probably be as small as you can go

Thanks for your reply. I am looking eventually for the smallest single/Multicolor LED that will go on a PCB. For Now I will be using the Breadboard and the 3 mm LED