Because of so many questions from beginners about paper type to use for paper modeling so I try to explain it in this article. The fact is, there is no such special paper for paper model. You can use any kind of paper that available on you, however every paper type has its own plus and minus. When you are going to make a paper model you should know the size of the built model, large size will need more thicker paper than the smaller one. Also there are some paper that can be printed with home printer (inkjet printer) but some don't, it must be printed with laser, offset printer or digital printing.
Now, paper size. Standard size for paper model is A4 and US Letter. Most of latest Paper Replika templates are in A4, but the old ones are in Letter, but some of them have been converted to A4. The big sized paper models that are using A4 : Optimus Prime detail (1 meter /3.3 feet), 1:1 Assault Rifle and others.