The following table compares the basic features of the various Arduinos and Arduino Compatibles mentioned in this guide. (click for a larger view).
For shield compatibility, be sure to check our Shield Compatibility Guide
*On the 32U4 processors there is some overlap between the Analog Input and Digital I/O pins, so the total number of I/O pins will be less than the sum of the two.
This guide was first published on Mar 23, 2013. It was last
updated on Mar 23, 2013.
This page (Arduino Comparison Chart) was last updated on May 04, 2015.
For some very nicely done pinout charts of several of these Arduino boards, go to: http://www.pighixxx.com/arduino/