I need to shrink an STL file below the 25 MB threshold, so I can open it in TinkerCad. I don't care about quality, I just need it shrunk.
How can I do this?
3D Printing Stack Exchange is a question and answer site for 3D printing enthusiasts. It only takes a minute to sign up.Sign up to join this community
If you have 3D software like Blender you can import your model and use the decimate modifier to lower the number of vertices and then re-export.
Here is a link to how you can do this: Simplify Geometry with the Decimate Modifier in Blender 2.9.
You can use Microsoft 3D Builder if you're under windows. It's a surprisingly powerful application that has basic but useful features. From there you can either resize the model to make it smaller or simplify it by lowering the triangle count.
Don't be fooled by the notion of it being a stock app, it's honestly the app I use the most when editing STLs.
Here's an example of an STL after being simplified alongside the original model: