Turn Your MacBook Trackpad into a Digital Scale
Ever wished you had a digital scale handy but didn’t want to buy one? Turns out, your MacBook’s Force Touch trackpad can do the job—with a little help from some clever code.
TrackWeight is an open-source macOS app that repurposes your trackpad’s pressure sensors into a functional weighing scale. It’s a fun hack that demonstrates just how precise Apple’s hardware really is.
What It Does
TrackWeight reads raw pressure data from your MacBook’s trackpad and converts it into weight measurements (in grams). The catch? You need to maintain finger contact while placing an object on the trackpad—since the sensors only activate when they detect capacitance (i.e., your finger).
Why It’s Cool
- No extra hardware needed – Just download the app, and your MacBook becomes a scale.
- Surprisingly accurate – The pressure readings are already calibrated in grams, so no complex math is required.
- A great example of hardware hacking – It uses the Open Multi-Touch Support library to access low-level trackpad data that macOS normally keeps locked down.
How to Try It
Option 1: Homebrew (Easiest)
brew install --cask krishkrosh/apps/trackweight
Option 2: Build from Source
- Clone the repo:
git clone https://github.com/KrishKrosh/TrackWeight.git - Open the project in Xcode, disable App Sandbox (required for trackpad access), and run it.
Usage Tips
- Keep your finger lightly touching the trackpad while placing the object.
- For best results, avoid metal objects directly on the trackpad (use a piece of paper as a buffer).
Final Thoughts
This is one of those projects that makes you appreciate the hidden capabilities of everyday hardware. While it’s not a replacement for a high-precision scale, it’s a clever proof-of-concept—and a fun party trick.
If you’re into hardware hacking or just love creative macOS utilities, give it a try. And if you tweak it to work even better, consider contributing back to the repo!
Got a cool project like this? Share it with us @githubprojects.