Just passed AZ-900 last week with an 847. I've been in IT support for 3 years but had zero cloud experience going in. Total study time was about 40 hours over 5 weeks - roughly 90 minutes per day on weekdays with longer sessions on weekends. The exam wasn't as intimidating as I expected once I got the core concepts locked in.
The cloud concepts section was almost entirely conceptual - CapEx vs OpEx, shared responsibility model, service types like IaaS vs PaaS vs SaaS. If you understand why each model exists and what problem it solves, the questions write themselves. I spent about 8 hours just on this section because it underpins everything else. For anyone starting out, the AZ 900 practice tests helped me identify which service category questions I kept getting wrong.
Azure architecture and services was the heaviest section for me by question count. Knowing the difference between Azure Blob Storage, Azure Files, and Azure Disk Storage specifically kept coming up in different phrasings. Don't just memorize names - understand the use case for each.
The identity and governance section was easier than I expected. Entra ID, RBAC, and the compliance frameworks like GDPR and ISO were all tested at a pretty surface level. If you're doing practice questions and scoring 80%+ consistently, you're ready to book the real thing.
No coding or hands-on lab component for AZ-900. Pure multiple choice. That makes it very prep-able compared to higher certs. 40 hours sounds right for someone without cloud background.
Azure Blob vs Files vs Disk tripped me up twice in practice. I made a simple comparison table for those three and the network storage options and drilled it until it was automatic. Worth 20 minutes of your prep time.
847 is a solid score. I passed at 790 and felt like I had maybe 5 questions I genuinely didn't know. The 700 passing threshold is accessible but don't walk in underprepared - some of the scenario questions require you to actually think through multiple services.
The CapEx/OpEx distinction shows up more than people expect and in different contexts. Really nail the logic behind it, not just the definition. I got three questions that were essentially the same concept reworded.