What is Qwiic?

The SparkFun Qwiic Connect System is an ecosystem of I2C sensors, actuators, shields, and cables that make prototyping faster and less prone to error.

Get it? It's quick Qwiic!

Benefits of the Qwiic Connect System

The Qwiic Connect System is designed to keep your projects moving.

The Qwiic Connect System uses the Inter-integrated Circuit (I2C) Protocol. I2C protocol is intended to allow multiple “slave” digital integrated circuits (“chips”) to communicate with one or more “master” chips with a mere two wires. We've adapted that technology to unlock the following benefits:

  1. No soldering between Qwiic breakout boards
  2. Polarized connectors to prevent mistakes
  3. Daisy chain capabilities to quickly add functionality

Keep your soldering iron at bay.

Cables plug easily between boards making quick work of setting up a new prototype. We currently offer three different lengths of Qwiic cables as well as a breadboard friendly cable to connect any Qwiic enabled board to anything else. Initially you may need to solder headers onto the shield to connect your platform to the Qwiic system but once that’s done it’s plug and go!

Qwiic Cable and Board

Qwiic cables connected to Spectral Sensor Breakout

Minimize your mistakes.

How many times have you swapped the SDA and SCL wires on your breadboard hoping the sensor will start working? The Qwiic connector is polarized so you know you’ll have it wired correctly, every time, from the start.

The PCB connector is part number SM04B-SRSS (Datasheet) or equivalent. The mating connector used on cables is part number SHR04V-S-B or equivalent. This is a common and low cost connector.

JST Connector

1mm pitch, 4-pin JST connector

Expand with ease.

It’s time to leverage the power of the I2C bus! Most Qwiic boards will have two or more connectors on them allowing multiple devices to be connected.

Qwiic Line of Products

Qwiic was predominantly designed for sensors but we’re adding shields, sensors, actuators, and displays. You can also adapt your pre-existing SparkFun I2C products using the Qwiic Adapter.

Qwiic Ideation Kit

Qwiic Starter Kit

SparkFun Distance Sensor Breakout - 4 Meter, VL53L1X (Qwiic)

SparkFun RedBoard Edge

SparkFun Differential I2C Breakout - PCA9615 (Qwiic)

SparkFun Real Time Clock Module - RV-1805 (Qwiic)

SparkFun Grid-EYE Infrared Array Breakout - AMG8833 (Qwiic)

SparkFun Triple Axis Magnetometer Breakout - MLX90393 (Qwiic)

SparkFun VR IMU Breakout - BNO080 (Qwiic)

SparkFun Distance Sensor Breakout - RFD77402 (Qwiic)

SparkFun Triple Axis Accelerometer Breakout - MMA8452Q (Qwiic)

SparkFun Environmental Combo Breakout - CCS811/BME280 (Qwiic)

SparkFun Qwiic Shield for Arduino

SparkFun Spectral Sensor Breakout - AS7263 NIR (Qwiic)

SparkFun Spectral Sensor Breakout - AS7262 Visible (Qwiic)

SparkFun GPS Breakout - XA1110 (Qwiic)

SparkFun Qwiic HAT for Raspberry Pi

SparkFun Qwiic Shield for Photon

SparkFun Micro OLED Breakout (Qwiic)

SparkFun Human Presence Sensor Breakout - AK9753 (Qwiic)

Qwiic Cable Kit

SparkFun Qwiic Adapter

Qwiic Cable - Breadboard Jumper (4-pin)

Qwiic Cable - 500mm

Qwiic Cable - 50mm

Qwiic Cable - 200mm

Qwiic JST Connector - SMD 4-pin

Qwiic Cable - 100mm


Experimental Products: SparkX products are rapidly produced to bring you the most cutting edge technology as it becomes available. These products are tested but come with no guarantees. Live technical support is not available for SparkX products.

Air Quality Sensor (Qwiic) - SGP30

Qwiic Keypad

Qwiic Bluetooth - HM-13

RGB Sensor (Qwiic) - BH1749NUC

Qwiic MP3 Trigger

Qwiic Relay

SparkFun BlackBoard

SparkX Pro RF - RFM69 915MHz

SparkX Qwiic RF - LoRa®-enabled 915MHz

Qwiic Pressure Sensor - LPS25HB

Qwiic IR Array - MLX90640 110° FOV

Qwiic EEPROM - 512Kbit

UV Sensor (Qwiic) - VEML6075

Qwiic Transparent OLED HUD

Qwiic EEPROM - 512Kbit

Pressure Sensor (Qwiic) - MS5637

Qwiic OpenLog

Qwiic Module for Tessel 2



Connection Options

Any microcontroller with an I2C port will work with Qwiic. Currently, we offer 3 easy to use shields:

ESP32 Shield (SparkX Product)

For devices like the popular Arduino Pro Mini 3.3V and Teensy we recommend either cutting a Qwiic cable in two or using the Qwiic Breadboard Cable and soldering the cable to the four spots on your development board.

Arduino Pro Mini 3.3V using a 50mm Qwiic Cable and Teensy LC using a Qwiic Breadboard Cable

We found it made more sense to solder four wires into place rather than 24 male pins and 24 female pins onto a shield that cost a bit of money as well. Easier and cheaper FTW!

Need more than one connection? Consider soldering four wires to a Qwiic Adapter. You’ll have two Qwiic ports for less than $1.

Frequently Asked Questions

How much power can I use?

The very conservative max current on a Qwiic cable is 226mA[1]. If you want to push it, 28AWG is good for up to 1.4A for chassis wiring: “isolated, unbundled wire in free air, as per the Handbook of Electronic Tables and Formulas for American Wire Gauge”. We wouldn’t recommend pushing the cables to 1.4A but hundreds of mA should be fine.

What’s the Pinout Again?

All Qwiic cables have the following color scheme and arrangement:

  • Black = GND
  • Red = 3.3V
  • Blue = SDA
  • Yellow = SCL

What About the INT Pin?

We deliberately chose four conductors to increase usability of the interconnecting cables, minimize the cost of the connectors, and limit the PCB footprint. All boards with extra pin options (such as interrupts, address selection, power save mode, etc) will have those pins broken out to 0.1" holes so the end user can add extra connections as needed.

How far can I run the Qwiic system?

I2C stands for inter-integrated circuit and we’ve got a tutorial dedicated to it here. The bus was designed to communicate between ICs on a printed circuit board so it wasn’t really designed to go long distances. That said, we’ve successfully communicated with sensors and boards over I2C over 1 meter (~4 ft).

If you need to communicate with sensors or devices that are many feet or tens of feet away you may need to look into other protocols such as RS485 which is good up to about 1200m (4000ft).

Can I use Qwiic on my system?

Absolutely. We would be thrilled if you used a Qwiic connector on your board or product! You can use the name Qwiic without royalties or attribution.

The requirements to say that your board is Qwiic or Qwiic-Compatible:

  1. You must use the same style 4-pin connector, JST or equivalent. You may not use a 5-pin or a different size connector. This is to make all Qwiic boards and systems interoperable.
  2. Boards must be 3.3V. You may do on-board buck or boost to get to a different voltage (1.8V or 5V for example) but the board must have onboard translation circuitry to work at 3.3V.
  3. All cables must follow the same color scheme: Black for GND, Red for 3.3V, Blue for SDA, Yellow for SCL.
  4. For obvious compatibility reasons you must follow the same pin out: GND / 3.3V / SDA / SCL.
  5. You may have any number of Qwiic connectors on a board. We encourage having a 2nd connector on input and output boards to support daisy chaining but it is not required.

What about my 5V board?

We may implement a DC buck/boost board in the future, but, for now, Qwiic only supports 3.3V boards. Currently over 90% of our I2C products are 3.3V, and the technology market is accelerating this trend.

Works with Existing SparkFun I2C Boards

What if you already have a handful of SparkFun sensors and parts? SparkFun has been putting our standard GND/VCC/SDA/SCL pinout on all our I2C boards for many years. This makes it possible to attach an Qwiic Adapter that will get your SparkFun I2C sensor or actuator onto the Qwiic system.

Here is the list of the boards that have the standard I2C pinout and will work with the Qwiic adapter board: