What Window size does
Window size is a lightweight utility that reports the exact dimensions of your browser viewport in real time. It outputs both outer and inner width and height measurements, giving developers the raw pixel data needed to test how a layout responds as the browser resizes. The page also includes references to screen resolution detection and example code snippets for retrieving these values programmatically.
How to use the RapidTables Window size
- 1
Open the Window size tool on RapidTables
- 2
Observe the current Outer window size and Inner window size displayed on the page
- 3
Resize your browser window to see the values update dynamically
- 4
Use the reported pixel dimensions to assess layout breakpoints or viewport constraints
- 5
Refer to the included JavaScript examples if you need to integrate the measurements into your own code
Best for
Web developers and designers who need quick, accurate viewport measurements without opening browser developer tools, especially when testing responsive breakpoints or simulating different screen constraints.
Limitations
- Measurements reflect the current browser viewport, not full screen or device physical size
- No option to save or export the dimensions for later reference
- Results depend on the user's browser window state and operating system taskbars
Window size FAQ
- Can I use this tool to test my website on specific device sizes?
- The tool reports your current browser viewport size in pixels. While you can manually resize your window to approximate common device widths, it does not emulate fixed device resolutions or pixel densities.
- What is the difference between outer and inner window size?
- Outer window size includes the browser’s outer edges such as toolbars and window borders, while inner window size measures only the content area inside the browser window.
- Does the tool work if I have multiple monitors?
- It measures the size of the browser window currently in focus. If you drag the window to a different monitor, the reported dimensions will change accordingly.
- Is there a way to copy the measurements automatically?
- The page displays the values in plain text; you can select and copy the numbers manually, but there is no built-in copy-to-clipboard button.