Square Force-Sensitive Resistor (FSR) - Alpha MF02A-N-221-A01

Product ID: 1075


FSRs are sensors that allow you to detect physical pressure, squeezing and weight. They are simple to use and low cost. This sensor is an Alpha MF02A-N-221-A01 FSR with a 38mm square sensing region. Note that this sensor can't detect where on the square you pressed (for that, check out our ribbon soft pots or capacitive touch pad ).

FSRs are basically a resistor that changes its resistive value (in ohms Ω) depending on how much its pressed. These sensors are fairly low cost, and easy to use but they're rarely accurate. They also vary some from sensor to sensor perhaps 10%. So basically when you use FSRs you should only expect to get ranges of response. While FSRs can detect weight, they're a bad choice for detecting exactly how many pounds of weight are on them.

FSRs are made of plastic and the connection tab is crimped on delicate material. The best way to connect to these is to simply plug them into a breadboard or use a clamp-style connector like alligator clips, female header, or a terminal block. It is possible to solder onto the tabs but you must be very fast because if your iron is not good quality or you dally even a few seconds, you will melt the plastic and ruin the FSR! Don't attempt to solder directly to your FSR unless you are absolutely sure you have the skills to do so.

For a full tutorial with wiring diagrams, code examples and project ideas, please read the FSR tutorial page!

Technical Details

Revision History:

  • As of May 10, 2022 - we are stocking Alpha MF02A-N-221-A01 instead of Interlink FSR406. The FSR406 had a sensitivity range of 0.1 to 10N, the MF02A has a sensitivity range of 1 to 49N. For most sensing use cases these are equivalent sensors.


  • Length: 87.18mm/3.43
  • Width: 43.7mm/1.72in
  • Thickness: 0.55mm/0.0216in
  • Weight: 2.2g/0.07oz

Interlink has a handy FSR datasheet for a similar sensor that has explanatory diagrams for how FSRs are put together


Thin sensor that detects physical pressure.
Use a photoresistor to measure light with a BeagleBone Black