Arduino Buying Guide: Which Board to Get?

There are so many different kinds of Arduino boards out there that you’d be forgiven for getting confused. What should you buy? What is more suitable for your project? Let us help, with this beginner’s Arduino buying guide!

This guide is also available as a video:

There are literally hundreds of different types of Arduino and Arduino compatible boards, so we couldn’t cover them all. However, we can talk about the most common, most useful, and most widely supported.

Before we get started, if you only want a table of numbers, check out the Arduino list at Sparkfun. I will approach this from a different point of view: from the point of view of an Arduino beginner, looking for your first development board, or after finishing your starter kit.

The Clone Wars and Arduino vs. Arduino

A little note before we start. Prices are correct at the time of writing, and where possible links to AliExpress where you can buy Arduino compatible clones for a fraction of the cost of branded Arduino models.

It is important to understand that these are not «cheap Chinese knockoffs», at least not in any illegal sense. Most of the Arduino hardware is released under an open source license, which means anyone is free to make their own copies (and even add features missing from the original design) as long as they label it «Arduino compatible» and not «Arduino «. ‘(Which is a trademark).

If you buy an original branded Arduino, a significant portion of what you pay goes to the Arduino Foundation, which goes to fund educational programs and further develop the brand. Things got a bit more complicated with a recent trademark dispute where the «original» Arduino LLC (the one that owns arduino.cc and with which you are probably most familiar) can only use the Arduino trademark in America and was forced to rebrand as Genuino outside the USA. If you are buying a branded Arduino in Europe then chances are you are actually paying money to Arduino SRL (Arduino.org) an Italian company originally known as Smart Projects, which used to be solely in the manufacturing business.

Like I said — it’s messy — and you’ll save a lot of money if you just buy clones.

With that out of the way — please don’t start a comment war on this — let’s start.

United Nations

With clones under $3, the Uno, while not the first Arduino board, remains the most popular. It’s also the model you’ll find included with most starter kits, and for good reason. Now it’s Uno, which is the standard format for upgrade «shields», i.e. boards that offer additional functionality. you can connect on top, and can often stack with each other.

Arduino Guide - Uno

About the size of a credit card, it has 14 digital I/O pins and 5 analog pins, and runs on 5v. It can be powered by either a USB cable or up to 12V DC via a female connector.

At the heart of the Uno is an ATMEGA328P with 32 KB of program memory, which is small by today’s standards. At some point, you will probably reach this limit, but as a starting device for learning, the Uno is perfect.

Leonardo

Leonardo looks deceptively similar to Uno, even though they are completely different. While the Leonardo has the advantage of being able to emulate a USB device so you can create your own keyboard, for example, it also has a number of quirks and is not compatible with all Arduino shields.

I would advise beginners to stay away from Leonardo: you’ll just find something wrong with your code, and when you go looking for help, you won’t be able to find a solution. If you want the capability to show up as a USB device, you’ll probably want to grab the Pro Micro instead, which we’ll cover later.

Mega 2560

Mega is the next logical step up from Uno, and if you run into a memory limit or really run out of IO, then you’ll want to pick up Mega. Despite being twice the size of the Uno at around $6 per clone, the Mega has 256KB of memory as well as 53 digital I/O and 15 analog ports.

Arduino Manual - Mega2560

Like the Uno, it runs at 5V and has a built-in USB port and DC-to-DC converter, so it really comes in handy when the Uno isn’t big enough. The Mega is also compatible with most Arduino shields.

Pro Micro

With clones priced at around $4 each, the Pro Micro is physically tiny and has a built-in USB driver with the ability to become a USB HID (Human Input Device): this means you can create your own keyboard or game controller designs.

This is great for small projects, although it gives you a couple less IOs to play with; 18 total, some of which may be analog, and only 32 KB of memory.

Arduino manual - about micro

Unlike the Uno, it’s breadboard friendly, so you can solder on a few headers and it will fit neatly into your breadboard. It comes in both 5V and 3.3V versions so you can choose the one that suits your project best.

There are also Pro Mini or Nano, available in a similar tiny form factor, but they do not have a built-in USB driver and cannot emulate a USB device. I’m going to skip them because you probably already know if you want them, and if you don’t then you’re better off getting a Pro Micro given the slight price difference. One reason you might want to look into the $2 Nano is because you’ve finished your project and just want to put it in a tiny box and be done with it.

NodeMCU/ESP8266

It’s not actually an Arduino, but it’s Arduino-compatible with a slight modification to your software. Available for just $5, I previously referred to the Arduino-compatible NodeMCU development board as the «Arduino Killer». «.

Arduino Guide - Nodemcu

The only downside to working with the NodeMCU is that it runs on 3.3V and the pins don’t allow 5V, which means you’ll need either sensors specifically designed for that voltage or a logic level switch (which modifies the 5V signal). at 3.3 v one, and vice versa). By the time you’ve finished Uno in your starter kit, this probably won’t bother you.

Lilypad 328

The Lilypad costs about $4 each, which is a bit odd: a 5cm round board designed for wearable projects. Instead of pins, you get printed circuit boards, ideal for sewing with conductive thread. The Lilypad uses the same processor as the Uno, so it’s just as limited at 14 digital I/O pins and 5 analog, but also accepts 5V so should be compatible with any Uno project you find. Make sure you buy the Lilypad 328 version and not the 168 version and keep in mind that you will also need to buy a separate USB FTDI version as it does not include it.

Arduino Guide - Lilypad