Sd card size for raspberry pi 3 capacity wise is for normal cards 32GB. To use any SD card larger than 32GB you will need to format your SD card to FAT32. Raspberry Pi 3 is not able to boot from exFAT. The bootloader built into the Raspberry 3 cannot be updated to fix this either. It is built into the GPU.
Sd card size for Raspberry Pi 3
Can I use SDXC cards for my Raspberry 3?
No. Per definition SDXC is an SD card larger than 32GB and formatted with exFAT. You can use FAT32 filesystem for such large SD cards. If you got one of those cards you will need to reformat it.
Sd card size for raspberry pi 3 physical size
Only the Raspberry Pi A and B use full-size SD cards. The rest uses Micro SD Cards. Raspberry Pi A+, Raspberry Pi B+, Raspberry Pi 2 B, Raspberry Pi Zero and Raspberry Pi 3 B all uses Micro SD.
Sd card size for raspberry pi 3 larger than 32GB.
As mentioned above you need to format the card for FAT32. If you are running Linux or MacOS you are good to go. They got the tools you need built-in. Windows require you to download some extra tools to reformat your SDXC to FAT32.
How to format my SD Card with Linux or MacOS?
MacOS users can use the default MacOS Disk Utility. This tool is able to format the entire SD Card and select MS-DOS as a file format. While some places it is called MS-DOS and other places it is called FAT32. It should be the same thing.
Linux users can use gparted or mkfs.fat to format SDCX to FAT32
How to format my SD Card with Windows?
Download the SD Memory Card formatter from sdcard.org. You will also find instruction on their website on how to use it. It is available to all windows version from version 7 and newer. SD Memory Card formatter tool is also available for MacOS. But not really needed.
Is there an easy way to install the OS?
Yes. There is a tool called NOOB available on raspberry.org for Windows and MacOS. NOOB is easy to use OS installer for Raspberry. You can use it to install Raspbian. If you for some weird reason, just joking, would like Windows 10 IOT Core instead. IOT stands for Internet of Things. Noob will fix that too for you. Even Ubuntu Mate. Download it and give it a try. Will save you a ton of time.
Maybe you are into hardware emulating or retro computer, check out Raspberry Pi 3 UAE, emulating Amiga.