I applied online. The same day a recruiter reached out asking to answer a few technical questions via email. A day after I had replied, I was told I was moving forward to a phone screening. This was a mix of SQL coding and probability questions. I don't think I did great, but good enough to be moved forward to a second phone screening. This one was much more heavily geared towards machine learning. Essentially I was presented with a scenario (a typical "a software engineer hands you over a dataset") and we spent most of the interview brainstorming about how to go about analyzing and eventually building a ML model out of the data. A couple of days later I was told I was invited to Google Headquarters. They had a specialist help me with travel arrangements. All very simple and smooth, even when I asked to make changes to my original plan. One thing you have got to make sure you pay attention to is that commute is horrible and you need plenty time to get from the hotel to Google. Even 10 miles can take 40 minutes. The onsite interview was very intense. These are 45 minutes back to back interviews, 100% technical with no frills such as intros, what his job is, do you have any questions. They covered pretty much everything from basic probability, to machine learning, to coding (I chose Python), to sampling, A/B testing, time series, SQL,... Most folks were nice, I only got one person who gave me the impression he hated to be in that room spending time interviewing. This wasn't as hard as I thought it would be, yet the breadth of the knowledge makes it very difficult to prepare well. Some of these questions seem to be geared more towards newly grads. I got a couple of questions I would have nailed after I left college 10 years ago, but have not touched in a business setting for years. So, long story short, have your basics covered. The only thing I can complain of is the lack of time to ask questions. I literally had two people asking if I had questions while they were packing their stuff and leaving the room... One thing I was super impressed with was my HR person. Super friendly and helpful throughout.