User Agent Checker
Free user agent checker. See your complete browser fingerprint — browser version, OS, rendering engine, screen resolution, and timezone — exactly as web servers see you.
What is a user agent checker?
A user agent is a string that your browser sends with every HTTP request, identifying itself to web servers. It includes information about your browser name and version, operating system, and rendering engine. Web servers use this to serve appropriate content, while developers use it for analytics, compatibility testing, and debugging.
How to check your user agent string
A typical Chrome user agent on Windows looks like: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36. Despite looking like it says "Mozilla" and "Safari", this is Chrome — the format is a historical artifact of browser compatibility.
Why would I need my user agent?
- IP Whitelist Config Generator — Detect your IP and generate AWS, MongoDB, GCP configs
- Port Checker — Test if TCP ports are open on any host
- DNS Lookup — Query A, AAAA, MX, CNAME, TXT and NS records
- WHOIS Lookup — Find domain owner, registrar, and expiry date
- SSL Checker — Verify SSL certificate validity and expiry
- IP Location Map — Find any IP location on an interactive map
- HTTP Headers Checker — Inspect request and security headers
- Latency Test — Measure your RTT to major cloud regions
- User Agent Parser — Full browser and OS fingerprint breakdown
- IPv6 Detector — Check your IPv6 address and connectivity
Common user agent strings by browser
Every major browser sends a distinct user agent string. Chrome on Windows typically includes "Chrome/VERSION" and "Safari/537.36" for compatibility. Firefox uses "Gecko/20100101 Firefox/VERSION". Safari on macOS uses "Safari/VERSION" without a Chrome token. Mobile browsers include "Mobile" in the string.
Web servers and APIs often use user agent parsing to serve different content to mobile vs desktop users, block bots, and apply browser-specific workarounds. If you are building a web scraper or API client, set a descriptive user agent string to identify your application.
How to change your user agent for testing
In Chrome: open DevTools (F12) → three-dot menu → More tools → Network conditions → uncheck "Use browser default" under User agent → select or type a custom string. This lets you test how your website renders for different browsers and devices without changing your actual browser.
In Firefox: type about:config in the address bar → search for general.useragent.override → create a new string value with your desired user agent.
User agent questions
navigator JavaScript API. No data is sent to our servers. Your user agent string never leaves your device.