Check User-Agent Information — Browser, Device & OS Details
When you open the page, your current device’s User-Agent string is detected automatically.
View detailed information including the operating system, browser, rendering engine, CPU architecture, and device type.
Paste any string into the User-Agent Analyzer to inspect environments other than your current device.
You can also analyze User-Agent strings from server logs, crawlers, bots, APIs, or external devices.
If you need to check your network environment or IP range during debugging, you can also use the What Is My IP tool.
👉 Quick Access Link: https://vvd.im/agent
Analyze a User-Agent string to identify browser, operating system, and device details.
JSON Output
{}Understanding User-Agent Structure and Token Meanings
A User-Agent string follows a structured format.
A common example looks like Mozilla/5.0 (Operating System Info) RenderingEngine/Version Browser/Version.
Different rendering engines such as Blink, Gecko, and WebKit may handle CSS and JavaScript differently.
Understanding the structure of a User-Agent string can help with browser detection, debugging, environment-based handling, and server log analysis.
How User-Agent Strings Appear on Mobile Devices
On mobile devices, the User-Agent string may include the device manufacturer and model information.
However, many Android devices display K instead of the actual model name due to privacy and security policies.
On iOS devices, identifiers are usually shown as iPhone or iPad rather than specific hardware models.
Even without physical access to a device, you can often identify the browser and device environment using only the User-Agent string.
User-Agent Reliability and Spoofing Limitations
A User-Agent value is voluntarily sent by the browser and can be modified manually.
If the value is changed using developer tools or browser extensions, the server may recognize the request as coming from a different browser or device.
For this reason, User-Agent data alone should not be considered fully reliable for identifying the actual client environment.
For security-related validation, it is recommended to analyze additional HTTP headers together with the User-Agent.
Understanding the JSON Output Structure
After the analysis is complete, you can inspect the full parsed data inside the JSON Output panel.
The top-level fields include ua (original User-Agent string), client (bot detection and environment type), and parsed (detailed OS, browser, engine, and device information).
The JSON result is useful for validating User-Agent parsing, debugging browser-specific behavior, and automated testing. Results can be copied directly to the clipboard using the copy button.
Where User-Agent Information Is Commonly Used
User-Agent data is used for far more than simple browser detection.
For custom UI delivery, it can help provide platform-specific features or redirect users to services such as the App Store or Google Play.
In analytics, User-Agent data helps measure browser and operating system usage to prioritize compatibility and optimization efforts.
From a security and operations perspective, it is also used for suspicious access detection and policy enforcement.
Using it together with the Search Engine Bot IP Checker can help distinguish crawler traffic from real user visits.
Frequently Asked Questions
A User-Agent is a text string sent by a browser when making requests to a web server.
It usually contains information about the browser name and version, operating system, rendering engine, and device type.
Example: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36
When you open this page, your current device’s User-Agent is detected automatically.
You can check it instantly without developer tools or additional browser settings.
To inspect a User-Agent from another device or a server log, paste the string into the User-Agent Analyzer and run the analysis.
The analysis result includes details about the operating system, browser, rendering engine, CPU architecture, and device category.
- OS: Operating system name and version
- Browser: Browser name and version
- Engine: Rendering engine such as Blink, Gecko, or WebKit
- Device / Form Factor: Device category such as Desktop or Mobile
- Client Type: Standard browser, bot, or crawler
You can check this in the Client Type section.
If it is displayed as Human Browser, the request is recognized as a standard browser connection.
However, bots that spoof or modify their User-Agent may not be detected accurately. For security-focused bot detection, additional validation methods should be used alongside User-Agent analysis.
Yes. Paste a User-Agent string extracted from server logs into the User-Agent Analyzer, and it will be analyzed the same way as the current device.
You can also analyze multiple User-Agent strings one by one, making it useful for identifying traffic patterns, crawlers, or suspicious access behavior in server logs.
A User-Agent string contains information about the browser, operating system, and device environment, but it does not always reveal the exact device model.
In particular, many Android devices display generalized values instead of the real model name due to privacy and security policies.
In addition, because User-Agent values can be modified by the browser, they should not be relied on alone for security checks or user identification.
Knowing the customer’s environment — including browser, operating system, and device type — makes it easier to reproduce issues and identify their cause.
The same problem can behave differently depending on the browser or operating system being used.
You can copy the User-Agent string detected by this tool and share it with customer support for more accurate troubleshooting and assistance.