6 min read
2026-03-06
Analyzing User-Agent from server logs reveals:
Which browsers visitors use
The ratio of mobile to desktop traffic
Which operating systems are popular with the audience
| Bot | User-Agent Contains | Purpose |
|---|---|---|
| Googlebot | Googlebot | Indexing for Google |
| Bingbot | bingbot | Indexing for Bing |
| YandexBot | YandexBot | Indexing for Yandex |
| Googlebot-Mobile | Mobile + Googlebot | Mobile indexing |
User-Agent analysis helps detect:
Vulnerability scanners (Nmap, Nikto, SQLMap)
Automated parsers and scrapers
Suspicious requests with non-standard User-Agents
Server-side content adaptation based on User-Agent:
Serving WebP images for supporting browsers
Loading polyfills for older versions
Redirecting mobile users to m.site.com
Marketers use User-Agent data to:
Identify target platforms for advertising campaigns
Analyze the technical capabilities of the audience
Optimize landing pages for popular browsers
QA engineers check how a site works under different User-Agents by emulating various browsers and devices.
Analyze a string with the User-Agent Parser.
See also: MAC Address Lookup, IP Calculator