To fact-check an AI answer, open its cited pages, locate the evidence for each important claim, and check that the version, audience, and date match your question. A working link is only the start: the source must actually support the sentence beside it.
This guide follows a web-source verification workflow using a deliberately flawed example claim and a real Microsoft reference. The example was written for this article; it is not a captured response from a tested AI product. Sources were checked on September 9, 2026.
For checking a summary against a document you already have, use our AI document summary guide. Here, the task is to investigate an answer that relies on information from the web.
1. Separate the Answer Into Checkable Claims
Start with the statements that would change what you do: a deadline, a feature limit, a compatibility requirement, or a claim that something is available to everyone. Split a sentence containing several facts into separate items. Check words such as “all,” “always,” and “free” as carefully as the number or date.
Example claim to investigate: “Every edition of Windows 11 version 24H2 reaches the end of updates on October 13, 2026.”
There are three things to check: the version, the date, and whether the date applies to every edition. Finding the date somewhere on a Microsoft page would not verify the entire sentence.
2. Open the Source and Identify Who Published It
Follow the citation to the page itself. Check the address, publisher, title, and whether the page contains the promised material. A familiar logo on an unrelated domain is not enough. If the link is broken or opens an unrelated page, search the publisher’s own site for the named document and record the replacement link.
For a product’s support schedule, begin with the vendor’s documentation. For a claim about measured performance, look for the actual test and its methods; a product page cannot substitute for a benchmark. The best source depends on what you are trying to establish.
For this example, open Microsoft’s supported Windows versions table. Find the Windows 11 servicing-channel table and the row for 24H2.
3. Match the Claim to the Exact Row and Column
Read the column headings before copying a value. The same row may contain different dates for different editions. Follow footnotes and distinguish the regular servicing channel from separately listed LTSC editions.
- The Home and Pro group lists 2026-10-13 for 24H2.
- The Enterprise and Education group lists 2027-10-12 for 24H2.
- The table therefore does not support the example’s word “every.”
Checked wording: “Microsoft lists October 13, 2026 as the end-of-updates date for Windows 11 24H2 Home and Pro, and October 12, 2027 for 24H2 Enterprise and Education in the general availability channel.” Keep the edition and channel with the date.
This is a scope check: the cited source exists, but the original claim applies one group’s date too broadly. Other common mismatches include a paid-plan feature described as free, a mobile feature described as desktop support, or an announcement described as an already available feature.
4. Distinguish the Page Date From the Event Date
A publication date, a page’s last-updated date, and a product’s support deadline describe different things. Record when you checked the source as well. A recently updated page can still contain historical information; an older page can still state a future deadline correctly.
If two sources disagree, compare their versions, regions, plans, and publication context. Trace announcements back to the current product documentation. When the conflict remains unresolved, report both statements and the uncertainty instead of silently choosing the date you prefer.
5. Keep a Short Evidence Record
For each important claim, save the source URL, the section or table location, the relevant restriction, and your conclusion. Use labels that describe the evidence rather than an invented confidence percentage.
- Supported: the inspected source supports the exact claim and its scope.
- Needs qualification: the claim is supported only after adding a version, edition, region, or other condition.
- Contradicted: the source explicitly gives incompatible information.
- Unverified: you could not locate or access enough evidence. This does not establish that the claim is false.
Example record:
Claim: Every 24H2 edition ends updates in October 2026.
Source: Microsoft’s supported Windows versions page.
Location: Windows 11 servicing channels, 24H2 row.
Finding: Edition groups have different dates.
Decision: Replace the broad statement with the edition-specific wording above.
Checked: September 9, 2026.
6. Recognize Checks That Do Not Prove the Answer
Asking the same assistant “Are you sure?” is a follow-up, not independent evidence. Agreement from another assistant also needs source checking. Several articles repeating the same announcement may all trace back to one source; count the underlying evidence, not the number of similar pages.
A calculator can check arithmetic, but it cannot establish whether the inputs came from the right population, year, or unit. Likewise, a citation can help you locate evidence without proving that the AI interpreted it correctly.
Anthropic’s guidance on reducing hallucinations recommends grounding claims in supporting material and allowing uncertainty, while noting that these measures do not eliminate errors. Use AI to organize the review; make the final comparison with the original evidence yourself.
7. Use the Checked Version and Keep Open Questions Visible
Replace an unsupported generalization with the narrowest wording the evidence supports. Remove a nonessential claim you cannot verify. If an unresolved fact is essential to a decision, keep the decision open until you have the needed evidence.
Keep the original answer and your evidence record together so you can see what changed. For information that changes over time, revisit the primary source before reusing the answer. A verification record explains what you checked on a particular date; it is not a permanent guarantee.
For the Windows example, our 24H2 Home and Pro upgrade guide covers the next practical steps. To make future requests easier to inspect, use our AI prompt-writing guide and specify that factual claims need sources and missing evidence must stay visible.