This browser information detector is simple yet comprehensive. All information is detected and displayed automatically when you open the page. Here is a detailed guide:
Once you open this tool, all browser and device information is automatically detected and displayed without any manual action. The detection runs entirely in your browser—the navigator and window object properties are read and displayed directly on the page. No data is uploaded to any server.
The "User Agent Full String" area at the top of the page shows the raw UA string that your browser sends to servers. Click the "Copy UA" button to copy the full UA string to your clipboard, which is handy for development debugging, filling technical support forms, or configuring CDN rules.
If you adjust browser settings (such as zoom level or language preference) or switch device orientation, click the "Re-detect" button to refresh all detection items and get the latest browser environment parameters.
Results are organized into five categories: Browser & OS (name, version, rendering engine), Screen & Display (resolution, color depth, device pixel ratio), Hardware (CPU cores, device memory, touch support), Network & Timezone (online status, timezone, language preference), and Browser Features & APIs (WebGL, Service Worker, push notifications, etc.). Each item is clearly labeled with real-time values.
Browser information detection is widely used in web development and technical support. Here are some typical scenarios:
When building responsive websites, you need to understand users' screen resolutions, device pixel ratios (DPR), and viewport sizes to verify that media query breakpoints work correctly. This tool helps you quickly obtain these parameters and determine whether layout issues are caused by specific device environments. Additionally, debugging related to navigator.userAgentData and Client Hints can also be aided by this tool.
When users report website malfunctions, support staff typically need to know the user's browser version, operating system, and supported APIs. Ask users to screenshot or copy the results from this tool to quickly determine whether the issue is caused by an older browser lacking support for a specific Web API (such as WebGL 2.0, Clipboard API, or Web Share API).
When using CDN services like Cloudflare or AWS CloudFront, you often need to configure content distribution rules based on User Agent or Accept-Language headers. The UA string and language preferences shown by this tool help you verify whether your CDN edge rules correctly identify visitor characteristics, ensuring users in different regions receive the appropriate localized content.
Browsers expose a significant amount of device information through JavaScript, which can be used for browser fingerprinting. By reviewing how much information your browser exposes through this tool, you can assess your digital privacy exposure level and consider installing privacy protection extensions (such as uBlock Origin or Privacy Badger) or adjusting browser privacy settings to reduce identifiable characteristics.
The User Agent string was originally introduced by Netscape Navigator, with a format of Mozilla/[version] ([system info]) [platform info]. Due to historical reasons, modern browser UA strings generally contain strings like "Mozilla" and "KHTML, like Gecko"—not because they are based on Mozilla or Gecko, but for compatibility with legacy websites. Google is promoting the User Agent Client Hints (UA-CH) alternative, which removes detailed device information from the UA string and replaces it with HTTP request headers sent on demand.
window.devicePixelRatio represents the ratio of physical pixels to CSS pixels. On Retina/HiDPI screens, this value is typically 2 or 3. When responsive images use the srcset attribute, browsers select the appropriate image resolution based on DPR to ensure crisp images on high-definition screens without wasting bandwidth. For example: <img srcset="img-1x.jpg 1x, img-2x.jpg 2x">.
Traditional User Agent strings contain too much device information and can easily be used for passive fingerprinting. Chrome has supported User-Agent Client Hints since version 89, allowing websites to obtain streamlined browser information via HTTP headers (such as Sec-CH-UA, Sec-CH-UA-Platform, and Sec-CH-UA-Mobile) instead of parsing lengthy UA strings. Firefox and Safari are gradually adopting this standard, and UA strings will become increasingly simplified in the future.
No. This tool runs entirely in your browser. All information is obtained through JavaScript's navigator and window objects and is displayed directly on the page. No data is uploaded to any server. Everything shown is public information that any website can access.
User Agent is an identification string that browsers send to servers, containing browser name, version, operating system, and other details. Websites use it to determine what device and browser a visitor is using, so they can serve appropriate content or features. For example, mobile sites typically detect "Mobile" in the UA to redirect to a mobile-optimized page.
Browsers report the current viewport's CSS pixel dimensions, not physical pixels. If your system uses scaling (e.g., 125% or 150%), or if your browser zoom is not at 100%, the detected resolution will be lower than the monitor's physical resolution. Additionally, when the browser window is not maximized, the window size is shown instead of the screen size.
For security and privacy reasons, browsers do not expose specific CPU models, GPU models, or other sensitive hardware details. This tool can only access information publicly available through browser APIs, such as logical CPU core count (navigator.hardwareConcurrency) and device memory (navigator.deviceMemory), which are approximate values rather than exact specifications.
Frontend developers can use this tool to quickly understand target users' browser environments, debug responsive layout issues, validate User Agent strings, detect Web API compatibility, troubleshoot browser-specific bugs, and verify whether CDNs or proxies are correctly modifying request headers.
Different browsers implement Web API standards and expose different ranges of information. For example, Safari does not expose navigator.deviceMemory, and Firefox does not expose navigator.connection's effectiveType. These differences are precisely what developers need to pay attention to when performing cross-browser compatibility testing.
Yes. This tool uses standard Web APIs and works in any browser that supports JavaScript, including desktop and mobile versions of Chrome, Safari, Firefox, and Edge. Mobile browser detection results will include mobile-specific parameters such as device orientation, touch support, and mobile network type.
navigator.onLine can only detect whether the browser is connected to a network, not whether the network is actually usable (for example, connecting to a WiFi network without internet access may still show as online). More accurate network status detection requires combining fetch request timeouts or advanced APIs like navigator.connection.effectiveType.