Dev Turns MacBook Trackpad Into A Weighing Scale With A Free Open-Source App

Today, we start the news with something quite curious: Did you know that you can use your MacBook trackpad as a scale? Well, that’s quite impressive, don’t you think so? It’s all possible thanks to Krish Shah, a Canadian developer and blogger, who released an experimental macOS application called TrackWeight. The app utilizes the pressure sensitivity built into the MacBook’s trackpad to estimate weight and is now available as open-source software under the MIT License on GitHub.

TrackWeight works by interpreting pressure data captured through the Force Touch sensors. However, it requires a continuous finger touch during measurement to maintain the capacitive sensing necessary for operation. Shah notes that while this design might slightly impact measurement accuracy, the results have proven to be “pretty accurate” in practical use.

The app’s functionality is supported by a combination of development tools, including SwiftUI for the user interface and Combine for handling data flow. Shah also credits existing work by developer Takuto Nakamura (@Kyome22) and the Open Multi-Touch Support library, which enables access to detailed trackpad touch metrics like position, pressure, angle, and density.

I tested the accuracy by putting my MacBook on top of a weighing scale and recording a video while adding pressure, then comparing frames.

You can see it’s pretty accurate! pic.twitter.com/etP8qlrGCh

— Krish Shah (@KrishRShah) July 21, 2025

The app has limitations typical of experimental tools. It is most accurate with objects weighing a few tens of grams, and Shah has successfully tested it with items as heavy as 3.5 kilograms. However, using the app to weigh luggage or a person is strongly discouraged due to the risk of damaging the laptop.

TrackWeight is only compatible with MacBook models that include Force Touch trackpads—specifically, MacBook Pro (2015 or newer) and MacBook (2016 or newer) models. Users must ensure the object being weighed fits within the physical dimensions of the trackpad. Additionally, metallic objects may cause errors in reading due to false capacitive detection; Shah recommends placing such items on a paper towel to avoid misreadings.

Instructions for building and running the app are available on the GitHub page, but Shah emphasizes that TrackWeight is intended solely for educational and experimental use. It is not recommended for commercial applications or any context requiring precise or certified measurements.

In essence, TrackWeight is a clever, low-stakes hack that demonstrates the creative potential of Apple’s hardware — pushing the boundaries of what a laptop’s trackpad can do, while reminding users to exercise caution when repurposing devices in unintended ways.

Filed in Apple >Computers. Read more about Apple, Macbook Air and Macbook Pro.