Using the Python API, it's pretty simple:
from selenium import webdriver browser = webdriver.Firefox() print browser.binary.process.pid # browser.binary.process is a Popen object...
If you're using Chrome, it's a little more complex, you go via a chromedriver process:
c = webdriver.Chrome() c.service.process # is a Popen instance for the chromedriver process import psutil p = psutil.Process(c.service.process.pid) print p.get_children(recursive=True)