3D Design

While I never heard of TinkerCAD but you can make some nice looking 3D models with those sizes.

If you don't mind me asking. What are you trying to create?

 

I've worked with tinker cad for the purposes of 3d printing a variety of components. The program is great because it is simple to use, requires no installation, and usually gets the job done quicker than a more fully featured program. However, in my experience it is very limited in that it works mostly with simple geometries, so it is best used to create rough shapes which are then further customized in a different program. Tinker cad does have the option to extrude vectors, so if you are familiar with inkscape this functionality can be of great use (I used it to make a Batarang for my friend).