What is Yahoo Japan?
Direct Answer: Yahoo Japan Advertising Bot operated by Yahoo Japan Corporation for advertising purposes.
The Yahoo Japan Advertising Bot is a web crawler operated by Yahoo Japan Corporation. It is used for advertising-related activities. The bot uses various user-agents such as Y!J-BRU/VSIDX, Y!J-BRW, and Y!J-ASR. It does not follow robots.txt from the database.
User-Agent Identification
The following user-agent strings identify Yahoo Japan in your live traffic data:
Y!J-BRU/VSIDXY!J-BRWY!J-ASRY!J-MMP/dscvY!J-WSCY!J-BRJ/YATS crawlerY!J-BRY/YATSH crawlerY!J-BRZ/YATSHA crawlerYJ-SAD
robots.txt Rules for Yahoo Japan
Respects robots.txt: No
This bot does not commit to following robots.txt
Yahoo Japan does not officially follow robots.txt directives. The only reliable way to control access is through server-side blocking (IP filtering, user-agent rules in your web server config) combined with log monitoring to verify effectiveness.
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Crawl Behavior
Frequency:Not Documented
Request Pattern:Not Documented
Crawl Activity Index
Relative crawl activity for Yahoo Japan over the past 28 days. Higher values indicate increased crawling intensity compared to the period baseline.
View recent activity data (last 7 days)
| Date | Activity Index |
|---|---|
| Mar 26, 2026 | 88.0 |
| Mar 27, 2026 | 82.7 |
| Mar 28, 2026 | 83.1 |
| Mar 29, 2026 | 81.8 |
| Mar 30, 2026 | 87.3 |
| Mar 31, 2026 | 90.2 |
| Apr 1, 2026 | 88.8 |
Source: Cloudflare Radar
Why track Yahoo Japan traffic?
Verify ad system crawling behavior. Yahoo Japan evaluates your pages for ad targeting, quality scoring, and policy compliance.
Optimize ad delivery. If Yahoo Japan can't properly access certain pages, ad targeting and revenue may be impacted. Log monitoring confirms accessibility.
Log Verification
To verify Yahoo Japan traffic in your live traffic data:
- Search access logs for the user-agent strings listed above
- Check if the IP addresses match documented ranges (if provided by Yahoo Japan Corporation)
- Verify the crawl pattern matches documented behavior
- Use reverse DNS lookup for additional verification if available
Note: Observed behavior in production environments may differ from official documentation. Live traffic monitoring provides the only reliable verification of actual bot behavior.
Undocumented Information
The following information is not officially documented for Yahoo Japan:
- crawl frequency
- IP verification
- JavaScript rendering
- official quotes
Official Documentation
View Official Yahoo Japan Documentation →
Information sourced from official documentation. Content generated with AI assistance.