
Overview
We've taken the original Circuit Playground Classic and made it even better! Not only did we pack even more sensors in, we also made it even easier to program.
Adafruit Circuit Playground Express is an all-in-one design board featuring a processor, sensors, LEDs, USB, and more, making it an ideal introduction to electronics and programming. Circuit Playground Express currently supports programming via Microsoft MakeCode, a web-based code editor for physical computing.
Using MakeCode's visual block-based editor, or its JavaScript editor, users can build programs to create custom animations, sounds, and use sensor events like "On Shake" to react to external stimulus.
The Circuit Playground Express is based on an ultralow-power SMART SAM L21 Microcontroller, using a 32-bit ARM® Cortex®-M0+ core.
The SAM L21 features sophisticated power management technologies, allowing for very low current consumption.
It can be powered from USB, "AAA" battery pack, or with a Lipoly battery. The round, sensor-packed Circuit Playground Express Board features alligator-clip pads around the edge, making it easy to connect to projects without having to solder.
Built-in USB allows quick connectivity for programming, with no special cables or adapters required.
Get Inspired
This project detects water leak and records the temperature and humidity reading at the time of leak and sends it to the Adafruit cloud.

By popular demand, we are pleased to announce that it’s now possible to buy the Arduino MKR IoT Carrier. Originally forming a key part of the Arduino Oplá IoT Kit, we’ve responded to our community to make the carrier available on its own, thus enabling you to benefit from having a bunch of sensors, actuators, and a display all featured on the one board — making it quicker and easier to take your IoT projects to the next level. Featuring a large set of built-in sensors and actuators as well as a useful color display, the carrier lets you focus on prototyping your IoT ideas right away by saving on the hassle of wiring and soldering these components. The carrier can become a WiFi, LoRa, NB-IoT or GSM-compatible device by seamlessly connecting to any MKR family board. Building a user interface for these boards is easy with the embedded color OLED screen, five capacitive touch buttons, and the five RGB LEDs. The integrated sensors (temperature, humidity, pressure, RGBC light, gesture and proximity) allow you to map the environment around the carrier, and should you need to capture any other data there are over 100 additional Grove sensors that can easily be connected directly to the carrier. Here’s are quick demo of the carrier's capabilities! (Special shout out to Mirko Pacioni and Filo Connesso for creating this demo.) Capture and store all the data locally on an SD card, or connect your MKR family board to the IoT Cloud for real-time data captured, storage, and visualization. The MKR IoT Carrier features: Round OLED displayFive RGB LEDsFive capacitive touch buttonsOn-board sensors (temperature, humidity, pressure, RGBC light, gesture and proximity)BuzzerIMU (Three-axis accelerometer sensor and three-axis gyroscope sensor)Two 24V relaysMicroSD card holder (SD card not included)Plug-and-play Grove connectors for external sensors — two analog and one digital (I2C)18650 Li-ion rechargeable battery holder (battery not