We're going to compare each of the Arduino Boards available to Maker's and Electronics Enthusiats. We'll discuss the features of each board, provide an informative pinout diagram with tonnes of detail, and toward the end of the article, provide a tabulated version of the information for quick reference. There are a bunch of Arduino boards, they come in different shapes and sizes, with different processing power, digital IO, and other capabilities. Rather than telling you guys what to buy, we have put together a handy guide to show you the capabilities of each board. The links below will take you to the relevant board with some really informative pinout diagrams linked with each board, if you want a tabulated specifications for easier comparison, you'll find them at the bottom of this article: Uno r3 Leonardo Micro Nano Mini Mega Due M0 Pro Esplora Yun Mini Arduino Uno Uno literally means one in Italian and is the entry-level Arduino board. Now at revision 3, the Uno has everything you need to get started with maker electronics. An ATmega328 8-bit microcontroller at the heart of the Uno provides: 16 MHz Clock 32 KB Flash Memory 2 KB SRAM 14 Digital I/O Pins with internal pull-up resistors (disabled by default but can be enabled with input_pullup command) 6 Analog input Pins, a 10-bit resolution on each pin. All the IO pins are connectable via the 0.1" pin headers. 20mA maximum current draw per pin, 200mA maximum for ATMega328 package. Powered via USB (5V @ 500mA) or using the Centre positive 5.5mm/2.1mm Barrel Jack connection. With the DC Barrel plug, you'll want to use a 9-12V @ 2A DC supply such as this one This board is a perfect choice for beginners. A removable microcontroller unit means if you damage the MCU while you prototype, you can easily replace it. Most SHIELDs are made for use with the Uno too, this means you get direct plug-n-play compatibility between the controller and the shield. The Uno also has optional revisions with Wi-Fi enabled, a surface-mounted ATmega328 option and a POE enabled and non-POE enabled Ethernet capable Uno. This particular board is the crowd favorite for experienced Arduino users and n00bz alike, and it's definitely the most popular of all the boards. This Arduino Uno Pinout is licensed as CC Share-Alike, created by Alberto from http://www.pighixxx.com Arduino Leonardo A board with built-in USB compatibility, more Analog inputs and Static RAM than the Uno? AND you can pick one up for less than the price of a standard Uno? Sounds great to us! Moving away from the ATmega328, the Leonardo features an ATmega32u4 MCU, which adds USB support to the MCU. 16 MHz Clock 32 KB Flash Memory 2.5 KB SRAM 20 Digital I/O Pins 12 Analog Input Pins, 10-bit resolution on each pin. 20mA max current draw per pin, 7-12V DC Input voltage. Like we mentioned above the 32u4 the Leonardo runs on, boasts its own USB support, this eliminates the need for the secondary processor chip the ATmega328 relies on for USB data transfer. If you find yourself needing a couple more IO pins, USB keyboard or mouse recognition as well as all the features of an Uno, then the Leonardo may be just what your project requires. The Leonardo also uses a Micro-B USB cable for connection to your PC, which is a step away from the USB Type-B connection we see on the Uno. If you're need them, or just want to take a look you can find the datasheet for the 32u4 here. This Arduino Leonardo Pinout is licensed as CC Share-Alike, Created by Alberto from http://www.pighixxx.com Arduino Micro This tiny board is designed to fit on a solderless breadboard. As it runs on the same 32u4 as the Leonardo, it has all the features of the Leonardo (which had everything the Uno did...). The big difference is the physical size of the board, going from 53mm x 68mm to 18mm x 48mm. 16 MHz Clock 32 KB Flash Memory 2.5 KB SRAM 20 Digital I/O Pins 12 Analog Input Pins, 10-bit resolution on each pin. 7-12V input voltage recommended 20mA max current per pin. Directly compared to the Leonardo and Uno, the Arduino Micro is smaller and has less power consumption, the board only uses 29mA. A major difference in supplying power to the board is the Micro has done away with the DC barrel jack, so you'll be using the Vin pins or the micro-B USB connector for a Micro based project. All in all the Micro is a great small-form-factor board for maker projects. This Arduino Micro Pinout is Licensed under a CC Share-Alike, Created by Alberto from http://www.pighixxx.com Arduino Nano The Nano is slightly smaller than the Micro and similarly, it has been designed to fit on a solderless breadboard. The Nano, however, runs on the ATmega328 MCU, the same chip used in the Uno. It uses a Mini-B USB Port, with the same barrel jack-less design as the Micro. 16 MHz Clock 32 KB Flash Memory 2 KB SRAM 14 Digital I/O Pins 8 Analog Input Pins, 10-bit resolution on each pin. Surprisingly, the Nano has more RAM than the Micro. This is due to the smaller bootloader on the ATmega328. All in all, the Micro and the Nano very similar boards with different brains. Again, the small form factor is the reason you would grab a Nano. This Arduino Nano Pinout is Licensed under a CC Share-Alike, Created by Alberto from http://www.pighixxx.com Arduino Mini When space is at a true premium, you won't find a smaller Arduino board than the Mini. At a minuscule 18mm x 30mm, the Mini still somehow provides 22 Digital IO pins. It's smaller than the Nano and packs almost identical specifications. Thoughtfully, Arduino designed the Mini to be just as easily plugged into a breadboard as the Nano/Micro form factor. 16 MHz Clock 32 KB Flash Memory 2 KB SRAM 22 Digital I/O Pins 8 Analog Input Pins This board is the ideal option for fitting a project into a tiny housing and with power requirements of 7-9V DC, you can easily add mobility to your project. The Mini does away with the ICSP header too, so you'll need to use a USB to TTL serial adapter on this one. Arduino warns that if you use more than 9V with the Mini you are likely to straight up kill the board, so bear that in mind if you go with this board. This Arduino Mini Pinout is Licensed under a CC Share-Alike, Created by Alberto from http://www.pighixxx.com/ Arduino Mega 2560 R3 The Mega Board runs on the ATmega2560 MCU, a step up from the 328p & 32u4. The Mega provides everything these other boards do, but adds a ton of extra pins to make bigger, more ambitious projects possible! CNC machinery, 3D Printing & Home automation can all require quite a lot of IO pins to get running. The Mega is the board for this very purpose. 16MHz Clock 256 KB Flash Memory 8 KB SRAM 54 Digital I/O Pins, 15 of these can be used with PWM. 16 Analog Input Pins Can be run with anything from 5-12V DC power. While the Mega 2560 is slightly heavier on the pocket than the smaller boards, the ridiculous amount of IO pins and SHIELD compatibility it comes with make it worth the money. A beefier brother to the Uno, this board is the go-to choice for larger projects. This Arduino Mega Pinout is Licensed under a CC Share-Alike, Created by Alberto from http://www.pighixxx.com Arduino Due This board is the biggest, meatiest board currently on offer to makers. Packing a 32-bit Atmel CPU with an impressive 84 MHz clock. This was the first Arduino board that used an ARM core CPU and it's go-to board for your more processing intensive 3.3V projects. 84 MHz Clock 512 KB Flash Memory 96 KB SRAM 54 Digital I/O Pins 12 Analog Input pins 2 Analog Output Pins, DAC1 & DAC2 pins use a DAC to provide 12-bit Analog outputs. There is one drawback of this board; the incompatibility with most shields due to the 3.3V Pin voltage. If you need to utilize 5V but still require a heavy hitting controller, perhaps the Arduino Mega would be the way to go. Where this board pulls ahead is the 130mA available on the dIgital IO pins. This Arduino Due Pinout is licensed under a CC No-Derivative-Works, Created by Rob Gray from http://www.robgray.com Arduino M0 (Pro) With the M0’s 32-bit MCU, makers rejoice at the opportunity to widen the scope of their products into IoT, wearables and beyond! With the higher processing power, the M0 can be a fantastic workhorse when the MCU of an ATmega328 doesn't cut the mustard. 48 MHz Clock 256 KB Flash Memory 32 KB SRAM 20 Digital I/O Pins 6 Analog Input Pins 1 Analog Output Pin Along with the 32-bit MCU comes the availability of a DAC for true 10-bit Analog output! The M0 only offers 3.3V pin voltages which make it incompatible with some shields. Arduino Esplora The Esplora is an interesting board from Arduino, the first thing you notice is its peculiar retro gaming pad shape. When you look a little closer it has sensors and joysticks attached to the PCB too. It's programmable, though, derived from the Leonardo it has most of the features you'd see on a Leonardo (minus the Digital IO) but with a few extras. 16 MHz Clock 32 KB Flash Memory 2.5 KB SRAM 7-12V DC Input voltage. Onboard sound, a joystick, a sliding potentiometer, a temperature sensor, an accelerometer, microphone and light sensor are all features that are built into the Esplora. The aim of this board was to let people get up and running without being caught up in the electronics of sensors and components. A great idea, however, nowadays there are better options for this kind of board. This Arduino Esplora Pinout is Licensed under a CC Share-Alike, Created by Alberto from http://www.pighixxx.com Arduino Yun Mini The Yun Mini is a tiny, breadboard sized PCB developed with an ATMega32u4 and an Atheros AR9331 processor combined. Operating at 400MHz and supporting a Linux operating system called Linino the Yun Mini is quite an impressive board. 400 MHz Clock 32 KB Flash Memory 2.5 KB SRAM 7-12V DC Input voltage. Inbuilt Wi-Fi 20 Digital IO Pins 12 Analog Input pins It stacks all the digital IO and features of a Leonardo but adds in Wi-Fi capability and Linux OS features. The board also uses a micro-USB connection and runs on a 5V input voltage. This Arduino Yun Mini Pinout is licensed as Creative Commons Share-Alike, Created by Arduino from http://www.arduino.org Table of specifications Hopefully, our nifty comparison table below helps to see the differences outlined above!