The following article is our English interpretation of an post originally published May 7th 2019 on Baidu Webmaster Help pages in Chinese language. If you'd like to check out the original article, you can find it here: https://ziyuan.baidu.com/college/articleinfo?id=1171Your website’s index count is the foundation of your search traffic. That’s why even a slight drop in index volume can be nerve-wracking for webmasters. A drop in index volume often leads to frantic diagnostics — and it’s a frequent hot topic in SEO circles.
This guide, curated by veteran webmaster and forum moderator Lao Lü, breaks down the most comprehensive list of reasons for index drops on Baidu — along with clear, actionable solutions.
1. Quick Reference: Baidu Index Drop Diagnostic Flowchart
(Note: Visual chart referenced in the original article not included here.)
2. Common Website-Related Causes of Index Drop
1. Inconsistent or Non-standard URL Structures
- Issue: The same content is accessible via multiple URLs (e.g., different domains, variations in capitalization, outdated URL rules).
- Fix: Choose a primary domain or canonical URL. Redirect all other URLs to it using 301 redirects. Submit the changes via Baidu’s URL revision tool.
External Platform Content Duplication
- Scenario A: You share your content with partner platforms or syndicate it manually — search engines may index the third-party site instead of yours.
- Fix: Use Baidu’s API submission tools to push new URLs first before syndicating elsewhere. Delay sharing if needed.
- Scenario B: Your content is being mirrored without permission.
- Fix: Secure your domain and server; use absolute URLs within your content and restrict access to a single valid domain.
2. Drop in Site Authority or Search Engine Trust
A. Content Issues
- Low-Quality Content: Avoid duplicate or thin content. Focus on original, well-structured, and valuable content.
- Irregular Updates: Reduced publishing frequency may reduce crawl quota.
- Fix: Maintain a steady publishing schedule and increase content freshness.
- Outdated Time-Sensitive Info: Regularly update and expand on time-sensitive topics.
- Harmful Content: Avoid spammy links, pop-ups, illegal or misleading content.
B. Algorithm Penalties
- Fix: Check Baidu Webmaster Tools for messages. Follow guidelines, correct issues, and submit feedback to lift penalties.
C. Suspicious or “Untrusted” URL Patterns
- Use tools to track indexability of specific URL patterns and correct indexing logic via sitemaps or direct submission.
D. Decline in Site Trust
- Unnatural Link Patterns (e.g., link farms): Only link to reputable sources.
- Sudden Theme Shift (e.g., from education to healthcare): 404 old content and notify Baidu before launching new content.
- IP/Domain Guilt by Association: If you’re on a shared IP with bad neighbors, consider migrating to a clean server or domain.
- Policy Restrictions: For sites hosted in politically sensitive regions (e.g., overseas servers), switch to a domestic, legally compliant hosting service.
3. Template or Site Architecture Issues
- Content Hidden Behind Logins or JS Triggers: Make content accessible to crawlers.
- Unfriendly Technologies: Avoid JavaScript or AJAX when serving critical content to crawlers.
- Responsive Design Issues: Ensure Baidu can distinguish between desktop and mobile versions using:
- Meta tags
- Separate URL patterns
- Clear HTML structure and labeling
4. Source Code Problems
- Major Errors or Code Changes: Severe code issues or large-scale structural changes can cause pages to be re-evaluated or dropped from the index.
- Title/Description (TD) Changes: If you change too many titles/descriptions at once, your pages may be temporarily de-indexed.
- Fix: Validate code quality. Keep internal links, URL structures, and tags stable. Gradually update TDs to align with user intent and content themes.
5. Previously Indexed URLs Now Behave Differently
- robots.txt Blocks: Make sure critical pages aren’t accidentally blocked.
- Broken or Changed URLs: Ensure case sensitivity and structure consistency during migrations. Use 301 redirects where necessary.
- Error Pages: If deleted unintentionally, restore the page. If intentional, submit as dead links before blocking via robots.
- Site Hacked: Prevent malicious redirects or content injection targeting Baidu crawlers.
6. DNS or Server Issues
A. DNS Problems
- Unstable or insecure DNS can block or mislead crawlers.
- Fix: Choose reliable DNS providers. Prevent frequent IP changes or malicious domain hijacking.
B. Server Accessibility
- Slow load times or regional inaccessibility can hurt crawlability.
- Fix: Ensure 3-second max load times across regions (ideally 1s), monitor uptime actively.
- Blocking Baidu IP/User-Agent: Use Baidu’s crawl diagnostic tools to ensure the crawler isn’t being blocked.
- Anti-spam Configuration: Segment bot traffic if needed, but verify that you’re not mistakenly blocking Baidu.
3. Baidu-Side Causes of Index Drop
1. Crawl Quota Redistribution
- Index slots are redistributed across similar content — some gain, others lose.
- Fix: Outperform competitors in content quality and structure to secure more index share.
2. Baidu Internal Data Errors
A. False Penalties from Algorithm Updates
- A new update may incorrectly penalize your site.
- Fix: Report the issue to Baidu and request a review.
B. Regional Crawl or Display Errors
- Baidu may misjudge your site’s performance due to partial data anomalies.
- Fix: Submit feedback to Baidu and ask them to verify crawler behavior across regions.
C. API/Data Loss/Backup Issues
- Errors in Baidu’s internal data handling.
- Fix: Contact Baidu and request internal data verification.