Hot Wheels/Matchbox vehicles scales
I think these die-cast vehicles are rarely any standard scale, although if the relative sizes of certain vehicles are close to each other then their Hot Wheels or Matchbox can be relatively close in scale to each other. They are made whatever size fits in the package, and the larger the real vehicle the smaller the scale will be for that model. Still, I often see HW or MB cars listed as certain scales by retailers or advertisers even though those models are not to scale. But, as was said earlier, there are some Hot Wheels that are made in specific scales.