Browser & Screen Info
Check screen resolution, viewport, pixel ratio and browser details
About the Browser & Screen Info
Front-end developers and QA engineers regularly need to know the exact environment their browser is running in: the actual screen dimensions, the viewport the page is rendered inside, the device pixel ratio that determines how many physical pixels back each CSS pixel, and whether the browser has cookies or touch input available. Collecting this information normally requires opening developer tools or writing console commands — this tool surfaces everything in one organised dashboard.
Web designers use it to debug responsive layout issues when a layout breaks at an unexpected breakpoint. Mobile QA testers use it to confirm that a test device's pixel ratio matches the assumed target in their test plan. Accessibility engineers check the reported language preference to verify content is served in the correct locale. All values are read directly from `window.screen`, `window`, and `navigator` APIs in your browser — no data is sent anywhere. The viewport dimensions update live as you resize the window.
How to Use the Browser & Screen Info
- Open the page and all values populate instantly from your browser's built-in APIs.
- Resize the browser window to see the Viewport Size fields update in real time, confirming responsive breakpoints.
- Click "Refresh" to re-read all values if you have changed a browser setting or switched tabs since loading.
- Click "Copy All" to copy the full dataset as a formatted JSON object — useful for pasting into a bug report or test log.
Why Use ToolForge’s Browser & Screen Info
- Live viewport updates: a resize event listener keeps the viewport width and height current as you drag the browser window, making it easy to pinpoint exact breakpoints without writing any JavaScript.
- Covers eighteen distinct data points including less-commonly checked values like hardware concurrency (CPU thread count), max touch points, and Do Not Track preference.
- Zero data transmission: every value is read from browser memory using synchronous JavaScript APIs. The page makes no network requests after the initial load.
- Formatted JSON copy: the "Copy All" button produces a compact JSON object with labelled keys, ready to paste directly into a bug report, test spec, or support ticket.
Frequently Asked Questions
What is the Device Pixel Ratio?
Device Pixel Ratio (DPR) is the number of physical screen pixels that correspond to one CSS pixel. A DPR of 2 means a "Retina" or high-DPI screen — a 1920×1080 CSS viewport is actually rendered at 3840×2160 physical pixels. Images need to be at least DPR× their displayed size to appear sharp on such screens.
What is the difference between Screen Resolution and Viewport Size?
Screen Resolution (from `screen.width` and `screen.height`) is the total number of pixels your monitor has. Viewport Size (from `window.innerWidth` and `window.innerHeight`) is the portion of that screen the browser's content area occupies, excluding toolbars and system chrome. Responsive CSS media queries target viewport size, not screen resolution.
What does Hardware Concurrency mean?
`navigator.hardwareConcurrency` reports the number of logical CPU threads available to JavaScript. Modern multi-core processors expose this to allow web workers to be spawned efficiently. A value of 8 means the browser can run 8 JavaScript threads in parallel, not that the machine has 8 physical cores (hyper-threading typically doubles the logical count).
Does this tool track or fingerprint my browser?
No. The values are read locally and displayed only to you. The tool makes no network requests with this data and stores nothing after you close the tab. The information displayed is the same information already available to every website you visit through standard browser APIs.
