Bot User-Agent Lookup
Paste any user agent string and find out instantly: is it a bot, which crawler is it, and what browser, operating system and device does it claim to be? Your own user agent is pre-filled below.
Common bot user agents (reference list)
These are the exact user agent strings the most important crawlers send today, from search engines like Googlebot and Bingbot to the new wave of AI crawlers such as GPTBot, ClaudeBot and PerplexityBot. Use them to test your robots.txt rules, server logs or firewall filters.
| Bot | Type | User agent string |
|---|---|---|
| Googlebot | Search engine | Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) |
| Bingbot | Search engine | Mozilla/5.0 (compatible; bingbot/2.0; +http://www.bing.com/bingbot.htm) |
| GPTBot | AI crawler | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko); compatible; GPTBot/1.2; +https://openai.com/gptbot |
| ClaudeBot | AI crawler | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com) |
| CCBot | AI crawler | CCBot/2.0 (https://commoncrawl.org/faq/) |
| PerplexityBot | AI crawler | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; PerplexityBot/1.0; +https://perplexity.ai/perplexitybot) |
| Bytespider | AI crawler | Mozilla/5.0 (Linux; Android 5.0) AppleWebKit/537.36 (KHTML, like Gecko) Mobile Safari/537.36 (compatible; Bytespider; spider-feedback@bytedance.com) |
| AhrefsBot | SEO crawler | Mozilla/5.0 (compatible; AhrefsBot/7.0; +http://ahrefs.com/robot/) |
| SemrushBot | SEO crawler | Mozilla/5.0 (compatible; SemrushBot/7~bl; +http://www.semrush.com/bot.html) |
| Amazonbot | AI crawler | Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/600.2.5 (KHTML, like Gecko) Version/8.0.2 Safari/600.2.5 (Amazonbot/0.1; +https://developer.amazon.com/support/amazonbot) |
| FacebookBot | Social | Mozilla/5.0 (compatible; FacebookBot/1.0; +https://developers.facebook.com/docs/sharing/webmasters/facebookbot/) |
| DuckDuckBot | Search engine | DuckDuckBot/1.0; (+http://duckduckgo.com/duckduckbot.html) |
How this user agent checker works
Your string is matched against a continuously updated open database of nearly 1,500 known crawler and bot patterns, covering search engines, SEO tools, uptime monitors, scrapers, social preview fetchers and AI training crawlers. If it matches, you get the bot's name and its official documentation link. If it does not, the string is parsed as a browser: name and version, operating system and device class, the same way analytics tools read it.
Remember the hard limit of every user agent check: the string is self-reported. Sophisticated bots copy real browser user agents word for word, which makes them invisible to this kind of lookup. Catching those requires network and behavior signals, datacenter IP ranges, proxy reputation, headless browser fingerprints, and interaction patterns. That is exactly what DevDome Bot Protection scores on every hit to your own site, against 650+ known crawler signatures and layered signals.
User agent FAQ
What is a user agent string?
A user agent is a short text label every browser, app and bot sends with each web request to identify itself. It usually names the browser and version, the operating system and the device type. Servers and analytics tools read it to decide what the visitor is, which is why checking a user agent is the fastest first step in telling humans from bots.
How can I tell if a user agent is a bot?
Legitimate bots identify themselves with a recognizable name and usually a URL, like Googlebot/2.1 (+http://www.google.com/bot.html). This lookup matches your string against a database of nearly 1,500 known crawler patterns, including search engines, SEO crawlers, scrapers and AI bots, and names the exact bot when it finds one.
Can bots fake their user agent?
Yes, trivially. A scraper can copy the exact user agent of Chrome on Windows and pass every user-agent check. That is why serious bot detection combines the user agent with network signals like datacenter ASNs and proxy reputation, plus behavior signals like missing JavaScript execution. DevDome Bot Protection scores every hit against 650+ known crawler signatures and layered signals instead of trusting the label.
What are the AI crawler user agents?
The big ones are GPTBot and OAI-SearchBot (OpenAI), ClaudeBot (Anthropic), Google-Extended (Google AI training), CCBot (Common Crawl), PerplexityBot, Bytespider (ByteDance), Amazonbot, Applebot-Extended and meta-externalagent (Meta). Each can be allowed or refused individually in robots.txt, and the table on this page lists their exact strings.
How do I block a bot once I know its user agent?
Polite bots respect a robots.txt Disallow rule with their user agent name. Impolite bots ignore robots.txt, so they need to be blocked at the server or edge, by user agent, IP range or ASN. DevDome Bot Protection does this per threat with one toggle and keeps legitimate search crawlers like Googlebot safe.
What is my own user agent?
This page fills the box with the user agent your browser is sending right now, so just open the page and press Analyze. You will see your browser name and version, your operating system and your device type, which is exactly what every website you visit can read.
Bot pattern data: crawler-user-agents (MIT). More free tools: Redirect Checker · SSL Checker · SERP Snippet Preview