I think this is neat, but only in a Rube Goldberg machine sort of way. The instructions are:
1. Open the scale
2. Rest your finger on the trackpad
3. While mainting finger contact, put your object on the trackpad
4. Try and put as little pressure on the trackpad while still maintaining contact. This is the weight of your object
That is, the pressure sensors only work if it detects capacitance, so you need to be touching the track pad (but not too much!!) while weighing something.
> TrackWeight utilizes the Open Multi-Touch Support library by Takuto Nakamura to gain private access to all mouse and trackpad events on macOS. This library provides detailed touch data including pressure readings that are normally inaccessible to standard applications.
How can something be available as a library but not as a native interface? Swift does not expose that API?
Have you done any testing to determine how precise and accurate this is? I suspect their must be a lot of variance between laptops, since this isn’t an intended use case.
OT, but this is what i love about apple laptop. They care about small detail, the detail that won't be on spec sheet for advertising.
Like their laptop speaker is superior to any other machine, even premium laptop like xps or surface won't even come close. Or their huge trackpad but still accurate.
TrackWeight: Turn your MacBook's trackpad into a digital weighing scale
(github.com)613 points by wtcactus 21 July 2025 | 147 comments
Comments
https://www.theverge.com/2015/10/28/9625340/iphone-6s-gravit...
1. Open the scale
2. Rest your finger on the trackpad
3. While mainting finger contact, put your object on the trackpad
4. Try and put as little pressure on the trackpad while still maintaining contact. This is the weight of your object
That is, the pressure sensors only work if it detects capacitance, so you need to be touching the track pad (but not too much!!) while weighing something.
How can something be available as a library but not as a native interface? Swift does not expose that API?
https://allthegooddomainsweretaken.justinmiller.io/2007/04/0...
Have you done any testing to determine how precise and accurate this is? I suspect their must be a lot of variance between laptops, since this isn’t an intended use case.
* Not legal for trade outside of Ankh-Morpork.
Like their laptop speaker is superior to any other machine, even premium laptop like xps or surface won't even come close. Or their huge trackpad but still accurate.
I wish other manufacturers copy this from Apple.
Does anyone know?