Study guide for Exam AI-900: Microsoft Azure AI Fundamentals

The answer

Before difficulty or prep time: one of these two exams no longer exists, and it is the one you passed.

Microsoft's AI-900 study guide, read 18 September 2026, carries this warning at the top of the page: "This exam was retired on June 30, 2026, at 11:59 PM Central Standard Time." — https://learn.microsoft.com/en-us/credentials/certifications/resources/study-guides/ai-900

Your certificate is not affected, and that is worth saying plainly before anything else. Microsoft's fundamentals certifications do not expire — our page states, from the same source family: "Microsoft fundamentals certifications do not expire. The retirement of the AI-900 exam is a separate matter from credential validity." (observed 2026-09-06). The exam is gone; what you earned by passing it is not.

What replaced it, if anyone asks you for the successor version. AI-901 is the named successor exam for Microsoft Certified: Azure AI Fundamentals — USD 99 for one attempt, United States proctoring region, observed 2026-09-04, passing score 700. One thing about it is worth knowing before you assume it is the same exam under a new number: our page's note is that Microsoft "expects Python coding knowledge, foundational technical skills, and familiarity with Azure resources. This is therefore not a purely nontechnical overview." (observed 2026-09-04). AI-900 was pitched at technical and non-technical candidates alike. AI-901 is not pitched the same way.

Now DP-900, which is the live half of your question. From Microsoft's own certification page, read 18 September 2026 (the page states Last Updated 07/21/2026):

• Price: "$99 USD*", with Microsoft's own asterisk: "Price based on the country or region in which the exam is proctored." So USD 99 is not your price until you check your region.
• Level: Beginner. Subject: Databases. Role: Data Engineer.
• Microsoft's stated expectation of you: "you should have familiarity with Exam DP-900's self-paced or instructor-led learning material", and familiarity with "The concepts of relational and non-relational data" and "Different types of data workloads such as transactional or analytical."
• And one line that answers a question you did not ask but probably should have: "You can use Azure Data Fundamentals to prepare for other Azure role-based certifications like Azure Database Administrator Associate or Azure Data Engineer Associate, but it is not a prerequisite for any of them."
• No retirement notice appears on that page as read on 18 September 2026 — unlike AI-900's, which carries one at the top.

On difficulty and prep time, which is what you actually asked — we will not give you a number, and here is why that is the honest answer rather than a dodge. Neither Microsoft page states a difficulty rating or an expected preparation time. Not found on the AI-900 study guide or the DP-900 certification page as read on 18 September 2026. What Microsoft publishes instead is scope — the skills-measured list — and a free practice assessment, which is a better instrument than anyone's estimate because it measures you rather than an average candidate.

The comparison that is actually available, and it is the useful one: both sit at the Fundamentals tier, both are priced at USD 99 before regional adjustment, and both are scoped by a published skills list you can read before paying. The difference is subject, not depth: AI-900 measured AI workloads on Azure; DP-900 measures core data concepts and Azure data services. Having passed one fundamentals exam, you already know what that tier feels like — which is a more reliable guide to your prep time than any stranger's answer in a thread.

What we have not established. No difficulty rating, no stated preparation hours, and no retake fee or retake waiting period for DP-900 were found in the sources reviewed on 18 September 2026. We hold no record for DP-900 at all — it is outside this registry's subject, and we are not the place to get its full terms.

What you can check yourself, and where — in this order: 1. Take Microsoft's free DP-900 practice assessment before you book anything. It is linked from the certification page and it answers your difficulty question about you. 2. Read the DP-900 study guide's skills-measured list beside the AI-900 one you already know, to see how much of it is new to you. 3. Check your own regional price, because of Microsoft's asterisk. 4. If anyone has asked you for "AI-900" specifically — a job posting, an employer, a training plan — tell them it retired on 30 June 2026 and that AI-901 is the named successor. That is the single most useful thing on this page for you, and nobody in that thread mentioned it.

No. Microsoft answers this question itself, as shown in the United States on 4 October 2026:

"No. Renewal does not apply to fundamentals certifications as they do not expire."

Microsoft's credential expiration policy says the same in one line: "Microsoft fundamentals Certifications do not expire."

What a retirement changes. Our page shows Microsoft retired the AI-900 exam on 30 June 2026 (facts checked 3 October 2026). The same policy separates an exam or credential being retired from it expiring:

"When a credential is retired, it will no longer be available for new candidates to earn. However, the credential will remain in the Active section of your transcript until it expires (if it has an expiration date) or for two years following the retirement of the credential (if it doesn't have an expiration date)."

So a retired fundamentals credential does not expire, and stays in the Active section of your transcript for two years after its retirement. The Azure AI Fundamentals certification page captured on 3 October 2026 still lists the certification, with "AI-901: Microsoft Azure AI Fundamentals" as its exam; the "Retirement date:" label under that exam carries no date in the captured page.

How this differs from role-based certifications, for comparison: "Why do role-based certifications expire after one year?" "Certifications expire after one year to ensure that tech professionals keep skills up-to-date with evolving technology." Their renewal is a test, and costs nothing: "No. Certification renewal is free to anyone with a valid Microsoft associate, specialty, and expert certification."

What was not found, bounded. Not stated on the three Microsoft pages reviewed on 3 and 4 October 2026: whether a fundamentals certification earned through AI-900 is the same credential as one earned through AI-901; where a retired credential is shown after its two years in the Active section.

What you can do.

1. Check your own transcript. Microsoft's FAQ gives the route: "Sign into your Learn profile, select the photo avatar, and choose Profile from the dropdown menu." Then "Choose Certifications inside the profile menu". A fundamentals certification has no expiry date to watch.
2. If an employer or school needs proof, share it while it sits in the Active section; for a retired credential that is two years from its retirement, per the policy above.
3. If you earned it through AI-900 and want to know where it stands, ask Microsoft's certification support: "My Azure AI Fundamentals was earned through exam AI-900. Is it the same credential as one earned through AI-901, and will it stay in the Active section of my transcript?"