US Citizenship and Immigration Services has a tool on their site that anyone may use to confirm their employment eligibility. When you go to the site: https://www.uscis.gov/mye-verify/self-check here is what you see:
When you click “start self check” you are taken to this screen:
This seems to indicate you must create an account, but if you scroll down a bit you’ll see there are some tools you may use without creating an account:
I clicked “self check” on the upper left portion of the window and it took me through a process in which I entered my full name, social security number and current address. It then gave me a short quiz (3 or 4 questions) about personal details known by the system, such as previous employers, phone numbers or other information that usually only the individual will know. After passing the quiz it did a check and confirmed my eligibility to work!