Hot to read a ".pbf" file on PC??

[gilbequick]

Old phone messed up trying to switch contacts to new Android phone. Old phone is unfortunately not usable. I backed up contacts on old phone and have them in a .pbf (not .pdf) stored on my PC, but I can't open the file to read it.

How do I open up a .pbf file?!?! I've searched and can't find a program to open it. Need Help!!