I often need to export my assets in multiple sizes. The ‘1x’ and ‘2x’ option in Sketch simply isn’t enough, as I sometimes need the same icon in let’s say 200×200, 300×300 and 400×400 while the original artboard might be 800×800.
Is there a way to export the contents of an artboard at a certain size?
Scaling isn’t always easy in Sketch as things like text etc don’t scale.
You can use fractions in export dialog.
And since you can export slices (which are like bounding boxes of sorts, for export purposes), which size you can define as you want, it’s easy to define a slice – based on your example – on 1000×1000 dimensions, and export it as 0.2x, 0.3x, 0.4x and 0.8x.