A Step-by-Step Framework for Diagnosing Schema Markup Problems

This guide is written for SEOs and site owners who are dealing with one of three specific situations:

• Rich results that dropped: You had star ratings, FAQ dropdowns, or sitelinks searchboxes appearing in search, and they disappeared — either gradually or after a specific site change.
• Rich results that never appeared: You implemented schema markup weeks or months ago and have seen no change in SERP appearance, despite the markup appearing to validate.
• Pre-launch or pre-migration auditing: You're moving to a new CMS, redesigning your site, or launching a new section and want to confirm schema is intact before and after.

This is a diagnostic guide, not an implementation guide. If you're starting schema markup from scratch, the implementation checklist in this cluster is the better starting point. This guide assumes markup exists and something is wrong — or you need to verify nothing has silently broken.

The diagnostic process here applies regardless of schema type — whether you're auditing Product, Article, LocalBusiness, FAQPage, HowTo, or any other markup. The tools and steps are the same; what changes is which properties matter for each type's rich result eligibility.

One important framing note: passing validation is not the same as being eligible for rich results. Google's documentation is explicit that satisfying technical requirements is necessary but not sufficient. Quality signals, content relevance, and algorithmic judgment all factor into whether eligible markup actually renders in search. This guide focuses on what you can diagnose and fix — not on factors outside your control.

Before running any tool, it helps to understand that almost every schema markup problem traces back to one of three root causes. Knowing which one you're dealing with determines which diagnostic steps matter most.

1. Validation Errors

These are syntax problems — malformed JSON-LD, unclosed tags in Microdata, incorrect property names, or values in the wrong format. Validation errors typically produce explicit error messages in Google's Rich Results Test and in Search Console. They're the most straightforward to diagnose because the tooling tells you directly what's wrong and often where.

2. Eligibility Failures

These occur when markup is technically valid but the page or content doesn't meet Google's additional requirements for a specific rich result type. Common examples include: an Article schema on a page with thin content, a Review schema that violates Google's review snippet guidelines, or a Product schema missing the required offers property. The markup validates clean, but no rich result appears. This is where many diagnostics stall — the tools say "pass" but the SERP shows nothing.

3. Implementation Drift

This is the most frequently missed cause. Markup was correct when it was implemented, but a subsequent change — a CMS update, a theme change, a migration, a new page builder, or a template edit — overwrote or removed it. The markup either disappears entirely or gets corrupted in ways that aren't immediately obvious. Search Console may lag days or weeks behind, meaning the error signal arrives well after the causal event. Without monitoring between audits, implementation drift can go undetected for months.

Most audits should check for all three in sequence, starting with validation errors (fastest to confirm), then eligibility, then drift investigation if the first two come back clean.

Work through these steps in order. Each step either confirms or rules out a root cause before you move to the next.

1. Pull the Search Console Rich Results report. Navigate to Search Appearance → Rich Results in Google Search Console. Review which markup types have errors versus warnings, and which URLs are flagged. Note the date errors began — this often correlates with a site change. Download the error URL list before proceeding.
2. Validate affected pages individually. Run flagged URLs through Google's Rich Results Test. This tool renders the page as Googlebot sees it, extracts all structured data, and checks each schema type against eligibility requirements. Note: it checks one URL at a time, so prioritize your highest-traffic affected pages first. For broad audits across many URLs, this step requires automation or sampling.
3. Compare markup against Schema.org specifications. For each schema type in scope, open the Schema.org documentation and verify that all required properties are present and correctly formatted. Then check recommended properties — these don't block rich results but affect how complete they appear. Common gaps include missing datePublished on Article, missing ratingCount on AggregateRating, or missing image on Product.
4. Inspect the rendered DOM, not just the source. JavaScript-rendered schema is a frequent silent failure point. View page source may show the markup, but if it's injected via JavaScript after initial load, Googlebot may not be processing it. Use Google's URL Inspection Tool in Search Console (Live Test) or the Rich Results Test to confirm the markup is present in the rendered version.
5. Check for implementation drift by comparing current markup to a prior baseline. If you have a staging environment, a Git history, or a cached version of the page from before the problem started, diff the structured data. If no baseline exists, check your CMS changelog or deploy history for the date the errors began in Search Console.

After running the steps above, use this decision tree to interpret what you found and determine the right remediation path.

Search Console shows errors → Rich Results Test also shows errors

You have a validation error. The error messages in the Rich Results Test will identify the property and the problem. Fix the markup at the source (your CMS, plugin, or code), re-validate, and request re-indexing via URL Inspection. Expect Search Console to update within days to a couple of weeks.

Search Console shows errors → Rich Results Test shows no errors

This usually means the markup was recently fixed but Search Console hasn't caught up, or the fix only applied to some URLs. Confirm the fix across all affected URL patterns, then monitor Search Console for the error count to decline over the following two to three weeks.

Rich Results Test shows no errors → No rich results in SERP

This is an eligibility failure or a Google algorithmic decision. Check Google's documentation for the specific rich result type you're targeting — confirm your content and page meet all stated requirements beyond the markup itself. For some types, like review snippets, eligibility also depends on content quality signals Google does not fully disclose.

Markup not found at all in rendered DOM

You're looking at implementation drift or a JavaScript rendering problem. Check when the markup was last confirmed present, review recent site changes, and inspect your CMS or plugin configuration. If the markup is JavaScript-injected, verify Googlebot is rendering it correctly using the Live Test in URL Inspection.

Markup present and valid on some URLs but not others of the same type

This points to a template-level issue — the markup is tied to a specific template or page type that isn't universally applied. Audit your template structure to understand which pages generate schema and which don't.

Different tools serve different stages of a schema audit. Using the right tool for each stage saves significant time.

For Initial Triage

• Google Search Console (Rich Results report): The authoritative source for understanding how Google sees your schema across your entire site. Start here every time. It surfaces errors, warnings, and valid markup by type, with URL-level detail.
• Google Search Console URL Inspection Tool: Run this on individual URLs to see the last crawl, rendered markup, and live test results. Useful for confirming a fix has been picked up.

For Page-Level Validation

• Google Rich Results Test: Tests a single URL or code snippet against Google's rich result eligibility requirements. Shows both the rendered structured data and any errors or warnings by property.
• Schema.org Validator: Tests markup for conformance with Schema.org specifications specifically — useful when you want to separate Schema.org compliance from Google's additional requirements.

For Scale and Ongoing Monitoring

Point-in-time auditing with individual URL tools only catches problems at the moment you look. For sites with hundreds or thousands of URLs, or for teams that need to catch implementation drift between manual audits, schema audit tools that automate validation across URL sets — and alert when markup changes or disappears — are the practical alternative to sampling by hand.

Automated monitoring doesn't replace understanding the diagnostic process. It surfaces the signal faster so you can apply the diagnostic framework when it matters, rather than discovering a six-month-old drift problem during a quarterly review.

For JavaScript Rendering Issues

• Chrome DevTools (Rendered Source vs. View Source): Compare the two to determine whether your schema is in the initial HTML or injected post-load.
• Screaming Frog (with JavaScript rendering enabled): Crawl-level audit of schema presence across your site with JS rendering toggled on and off, useful for identifying which URLs have markup and which don't.

Most schema markup problems are fixable within a standard workflow. But certain patterns indicate issues that warrant closer attention — either because they're harder to resolve or because they signal something wrong at the infrastructure level.

Rich results disappeared site-wide after a specific date

This is the strongest signal of implementation drift from a CMS update, theme change, or migration. The fix is rarely just correcting one URL — you need to trace the change event and fix it at the template or plugin level. Until the root cause is addressed, any individual URL fixes will be overwritten.

Markup validates correctly but rich results have been absent for more than 60 days

If you've confirmed valid markup, correct properties, and no eligibility violations, and rich results still haven't appeared after several weeks, you may be dealing with a Google-side algorithmic decision rather than a technical problem. This is worth noting in documentation rather than assuming the fix is still pending. Some content types and domains simply don't receive certain rich results regardless of markup quality.

Errors appear on URLs that weren't recently changed

If Search Console surfaces errors on pages that haven't been touched, it often means something changed at the infrastructure level — a plugin update, a CDN configuration change, or a server-side rendering issue. Audit your infrastructure changelog, not just the content.

Different validation results between tools

If the Rich Results Test shows a clean pass but the URL Inspection Tool shows missing markup, you likely have a caching or rendering timing issue. The live test in URL Inspection is closer to how Googlebot sees the page in real conditions.

When any of these patterns appear and the standard diagnostic steps don't resolve the issue, this is typically the point where bringing in structured data tools for ongoing markup monitoring — rather than episodic manual auditing — produces more reliable outcomes over time.