How fast airmail travel to aboard?

I believe it depends on where you sending it and the distance. If you use some private service , mail travels quite fast. For example US - Europe is about 4 working days. Withing the continent much faster. For other destinations eg. US - Australia it could take 1 week. All these estimates are valid for private services, where the cost is larger. For regular post-offices it could take from 1 till 4 weeks, always depending on distance.