Browser Info

Browser Info — What It Shows

This tool reads and displays all the browser and environment information exposed by your browser's JavaScript APIs — without sending anything to a server. Useful for developers debugging cross-browser issues, testing responsive designs, verifying timezone handling, or understanding what fingerprint data websites can access about your browser session.

Information Collected (Client-Side Only)

• User-Agent string — Browser name, version, OS, and rendering engine
• Screen resolution — Physical display dimensions in pixels
• Viewport size — Usable browser window dimensions
• Device Pixel Ratio — HiDPI/Retina display detection
• Timezone — IANA timezone from Intl.DateTimeFormat
• Language — Browser preferred language and locale
• Platform — Operating system as reported by the browser
• Connection type — Network connection speed tier (if available)

Common Developer Use Cases

• Verifying which browser and OS a QA tester or user is running when reporting a bug
• Checking DPR to understand if a Retina display is being used for image debugging
• Confirming timezone offset when debugging date/time display issues in international apps
• Inspecting User-Agent for browser detection logic and compatibility testing

Privacy Note

All data displayed here is read directly from your browser's JavaScript APIs (navigator, screen, Intl) and rendered locally. Nothing is transmitted to any server, logged, or stored. This is the same data any website you visit can already read from your browser.

Frequently Asked Questions

What information does the User-Agent string contain?

The User-Agent string identifies your browser and operating system to web servers. It includes the browser name and version (e.g., Chrome/120), the rendering engine (e.g., AppleWebKit), the OS and version (e.g., Windows NT 10.0), and sometimes device model on mobile. Developers use it to serve compatible content or log client environments.

Why might my timezone differ from my physical location?

Your browser reports the timezone configured in your operating system settings, not your physical GPS location. If you use a VPN, travel without updating system time, or have manually set a different timezone, the reported timezone will reflect your system setting rather than where you actually are.

What is the difference between screen resolution and viewport size?

Screen resolution is the total pixel dimensions of your physical display (e.g., 2560×1440). Viewport size is the usable area of the browser window where web content is rendered — it is smaller because it excludes the browser chrome (toolbar, tabs, address bar) and system taskbar. Web developers care more about viewport size for responsive design.

Can websites detect if I am using a private or incognito window?

Browsers do not expose a direct JavaScript API to reveal incognito mode. However, some detection techniques exist, such as checking storage quotas or the FileSystem API. These heuristics are unreliable and increasingly blocked by modern browsers. In general, incognito mode is not reliably detectable by websites.

What does the Device Pixel Ratio (DPR) value tell me?

Device Pixel Ratio is the ratio of physical screen pixels to CSS pixels. A DPR of 2 means one CSS pixel maps to a 2×2 grid of physical pixels — common on Retina/HiDPI displays. Web developers use window.devicePixelRatio to serve higher-resolution images to sharp screens and standard images to lower-DPI displays.