I did the Google UXD (product designer) interview for a senior/staff-equivalent role earlier this year. The design interview process at Google is genuinely different from most companies and I had to figure a lot of this out on the fly, so sharing the full picture.
First: the roles. Google has multiple design tracks. UXD is the primary product design track. There's also UXMS (motion/systems), UXES (emerging tech), and UX Research. Each has a slightly different loop. I'm covering UXD specifically.
Portfolio Review: This is the anchor of the loop and the most important prep surface. You get about 25-30 minutes to walk through 2-3 projects. They expect you to go deep on one rather than skim five. They care about: your specific contribution (not the team's), your decision-making process, what you would do differently, and how you measure success post-launch. Do not include projects where you can't speak precisely about your role. They will probe.
Design Exercise: A timed exercise, usually 45-60 minutes. You're given a prompt (something like: design a feature for Maps to help new users) and you walk through problem framing, user identification, how you'd research it, sketches/wireframes, and how you'd validate. There's no right answer. They're watching your process, your ability to narrow scope under time pressure, and whether you ask clarifying questions before diving in.
Interaction Design / Craft: A round specifically about the quality of your visual and interaction thinking. They may show you an existing Google product and ask how you'd redesign a specific flow. Or they'll ask about motion, states, edge cases. Figma prototyping fluency matters here.
Cross-Functional Collaboration: A behavioral round about how you work with PMs, engineers, researchers. They use the same STAR format. Have stories about navigating tension between design goals and engineering constraints, because that's a very real day-to-day at Google.
Compensation for senior UXD: my offer was around $260-280k TC depending on RSU performance. That's in line with what I'd seen for L5 equivalent on the engineering track.
The portfolio is 80% of the loop. I've seen strong designers fail because they showed breadth over depth. Pick two projects you can defend for an hour.