Reinstall OSX without having firmware password (but having root access to osx) I know that the question can sound suspicius but let me explain. I've installed in end 2015 a frash mac osx. I setted up the firmware password and never used again. Until today. The problem is: I forgot that. I know that I can go to an Apple Store or a certified shop and have it restored, but this requires me a lot of time (I'm far away from Apple Store and the neares shop told me they have to keep it for 10 days beacuse they have other pc to repair first..).

My goal is to reinstall a fresh Mac OSX (I do every year). Is this possible without having the firmware password? I usually do the Command+R and the proceed from there, but I can't beacuse I don't remember the password. 

I was wondering: if I download sierra installation can I run a fresh installation and erase all data?

PS: With the find my phone I can reset pc, but can I also reset the firmware password (I dubpt so)
There is nothing nicer than a fresh install, and the FW password was also an obstacle for me on my Mid-2012 Mac. After tinkering, I was able to erase my Mac to factory default and fresh install, but, this method does not reset the FW password. 

You will need: 
- An internet connection
- A second apple device connected to an Apple ID 
- Your Mac, connected to the same Apple ID with Find My Mac enabled.


Connect iCloud "Find My Mac"
Using another device, locate your Mac and find the "erase" option. 
Once your Mac has been erased, you should be taken to the recovery menu by default where you are able to install a fresh version of MacOS without the FW password.


This method will erase and restore your Mac to factory defaults, as if it were just out the box!

This was also my ultimate goal (security paranoia) and was relieved I did not have to go to apple and wait 10+ days for repair. 

Unfortunately, after days of googling, tinkering and having faith I would be the first to break the code.... I do not think there is anyway to reset the FirmWare PW unless you visit Apple.