The Nano Every is based on the ATmega4809 microcontroller running at 20MHz. This is broadly compatible with other AVR chips from Arduino, including the one in the original Nano.
This board is running at 5 V, so should be a completely drop-in replacement for the original Nano, but with more flash (48kB) and more RAM (6kB). At eight euros, this is the cheapest board that Arduino makes by a fairly significant margin.
The Nano 33 IoT also comes in the same form factor as the Nano, but it’s built on the 32-bit ARM SAMD21G18A microcontroller. It runs at up to 48MHz and has 256kB of flash and 32kB of RAM.
Overall, this is a significantly more powerful processor than the AVR chip in the Nano Every. As well as this, there’s an ESP32-based u-blox module for WiFi and Bluetooth, and a six-axis inertial measurement unit.
All this comes in at 16 euros, which is twice the cost of the Nano Every, but it’s still one of the cheapest boards that Arduino produces.
Both of these devices are tiny, solidly made, and as easy to use as you’d expect from devices made by Arduino. Unlike many small boards, there are four mounting holes, so you can easily secure the board in your projects.
They’re completely flat on the bottom, and have castellated pads so they can be soldered onto other PCBs to make a sort of permanent shield setup – a sign that Arduino is targeting the small-run electronics industry by making it easier to build products out of Arduino projects.
The world of small microcontrollers is pretty crowded at the moment, but these new Nanos do have their niche within it. They’re among the smallest boards around, yet still pack in quite a healthy amount of IO (12 digital, 8 analogue in, and 1 analogue out). They achieve this feat by cutting out one key feature found in most slightly larger boards – battery management.
You’ll need a source of power, whether via the USB port or up to 21 V via Vin. The rather beefy on-board regulator can provide up to 950 mA for peripherals.
In a world of 3 V microcontrollers, the Arduino Nano Every is probably one of the best choices for 5 V microcontroller right now from a price to performance ratio, as long as you don’t need battery charging or networking.
There is less 5 V hardware around these days, but if you find yourself needing to control some, this will save you the hassle of level shifting. With 950 mA of current available from the regulator, and 5 V IO, this is a great choice for small to medium-sized NeoPixel projects.
The Nano 33 IoT is in the fuller marketplace of 3.3 V WiFi-enabled development boards, but it does have a few stand-out features.
It’s the smallest, cheapest board that’s compatible with the Arduino IoT Cloud. While this online development environment is still in development, it’s shaping up to be a really easy way to get started with IoT devices.
The Nano 33 IoT has the sprightly performance that we’ve come to expect of boards based on the SAMD21 microprocessor, and the off-chip WiFi gives solid networking performance.
Verdict for the Arduino Nano Every: 9 out of 10
If you need a small, 5 V microcontroller board, this has to be top of your list.
Verdict for the Arduino Nano 33 IoT: 8 out of 10
A no-nonsense WiFi microcontroller that fits in the tiniest of spaces.