What Is My User Agent?
Your user agent string identifies your browser, operating system, and device when you visit a website. View it instantly below.
Detecting...
Why user agent data matters
User agent data is critical when building and testing cross-browser applications. It is frequently used during frontend optimization, compatibility checks, and device-specific debugging in modern web application development projects.
What is a user agent?
A user agent is a text string sent by your browser to websites and servers with every request. It identifies information such as the browser type, operating system, device category, and rendering engine being used.
Web applications rely on user agents to deliver compatible content, apply security rules, and troubleshoot platform-specific issues.
Why is my user agent important?
Your user agent helps websites and applications understand how to interact with your device. It is commonly used for:
- Detecting browser compatibility issues
- Debugging responsive and mobile behavior
- Applying device-specific features or fallbacks
- Identifying bots, crawlers, or automated traffic
- Diagnosing client-side rendering problems
- Logging request context for analytics and security
When do you need to check your user agent?
Checking your user agent is useful in many real-world scenarios, including:
- Web developers testing cross-browser behavior
- QA engineers validating device compatibility
- API teams diagnosing client requests
- Security teams analyzing suspicious traffic
- SaaS teams debugging customer environments
Can a user agent be spoofed?
Yes. User agents can be manually modified or spoofed using browser settings, extensions, or automated tools.
Because of this, user agents should never be used as the only security mechanism. Reliable detection requires combining user agent data with other signals such as IP behavior, request headers, and connection patterns.
User agent vs browser fingerprinting
A user agent provides declared information directly from the browser. Browser fingerprinting, on the other hand, combines multiple signals such as screen size, fonts, system capabilities, and hardware features to create a more unique profile.
This tool displays only your user agent and basic client information. We do not fingerprint, track, or identify users.
Frequently Asked Questions
No. All detection is performed in real time and is not stored or logged.
Yes. Your user agent is automatically sent with every HTTP request unless intentionally modified.
User agents include compatibility tokens to support older systems while identifying modern browsers.
Yes. Most browsers allow changing the user agent through developer tools or browser extensions.
Privacy Notice
All information shown is derived from your browser request and client environment. We do not collect, store, or share personal data.
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