My Screen Size

Open the tool and wait for the live display panel to appear. No measurements or device details need to be entered manually.

The large result shows the current screen width and height reported by the browser in CSS pixels. The cards below show viewport size, estimated device pixels, aspect ratio, DPR, color depth, and touch capability.

Resize the browser or rotate a supported device to watch the relevant readings update. Use Refresh when you want to request a new snapshot, Copy to place a complete text report on the clipboard, or Fullscreen to enlarge the panel.

The phrase screen size can mean either pixel dimensions or a physical diagonal. This tool reports browser-accessible pixel dimensions; it does not estimate how many inches or centimetres the display measures diagonally.

A dependable physical-size calculation would require accurate hardware dimensions or pixel density. Standard webpage APIs do not consistently provide that information, so the calculator does not invent a diagonal size or PPI value.

Screen resolution is the logical width and height exposed through the browser's Screen interface. The viewport is the interior layout area currently available to the webpage.

A screen can report 1,536 × 864 while the webpage receives a viewport of 1,200 × 700. Browser tabs, toolbars, side panels, developer tools, scrollbars, and a non-maximised window can all reduce the webpage area.

Use viewport dimensions when reproducing responsive breakpoints. Use screen dimensions when you need the logical display size reported to the browser.

Web layouts use CSS pixels. A CSS pixel is a logical browser unit and does not always correspond to one hardware pixel on a high-density or scaled display.

Device pixel ratio, usually called DPR, describes the browser-reported relationship between device pixels and CSS pixels. A DPR of 2 means the browser generally maps a two-by-two device-pixel area to one CSS pixel in each dimension.

The panel keeps screen resolution and estimated device pixels separate so a logical browser measurement is not mislabeled as verified hardware resolution.

Estimated device width equals the reported screen width in CSS pixels multiplied by DPR. Estimated device height uses the same calculation.

For example, 1,536 × 864 CSS pixels at a DPR of 1.25 produces an estimate of 1,920 × 1,080 device pixels.

The result is useful for understanding scaling and high-density rendering, but it does not prove that 1,920 × 1,080 is the panel's native resolution. Browser zoom, operating-system scaling, and privacy behaviour can affect the inputs.

Aspect ratio compares the reported screen width with its height and reduces the values to a simpler whole-number ratio. A 1,920 × 1,080 or 1,536 × 864 report reduces to 16:9.

Landscape means width is greater than height, portrait means height is greater than width, and square means the values match.

An unusual ratio is not necessarily an error. Display scaling, browser reporting, rotated devices, folding displays, and uncommon monitor shapes can produce less familiar values.

Color depth is the bit-depth value exposed by the browser. It is useful as an environment detail, but it does not measure color accuracy, gamut coverage, HDR quality, calibration, or how many colors the physical panel can truly display.

Touch support is inferred from touch-point and pointer-capability signals. It means touch-capable input was detected; it does not identify the device as a phone or tablet and does not prove the current display itself is touch-sensitive.

A laptop advertised as 1,920 × 1,080 can report 1,536 × 864 CSS pixels when operating-system scaling is set to 125%. In that example, a DPR of 1.25 produces a 1,920 × 1,080 device-pixel estimate.

Page zoom, display scaling, browser window size, mobile browser controls, developer tools, multiple displays, and privacy features can all change or limit what a webpage sees.

Treat the panel as a transparent report of browser APIs, not as a hardware-diagnostic certificate.

Developers can resize the browser and watch the viewport card while reproducing a breakpoint, debugging overflow, or checking how much layout space a page receives.

Designers can compare viewport size with DPR and estimated device pixels when preparing screenshots, canvases, or high-density graphics. Final exported-image dimensions should still be checked in the capture or design application.

Support teams can copy the display report and attach the measurements to a bug report without asking the user to find values in operating-system settings.

The browser can expose useful layout and display-context values, but it is intentionally not a complete monitor inventory system.

The tool avoids fake precision: it does not calculate physical diagonal, PPI, monitor model, panel type, serial number, exact refresh rate, color calibration, or guaranteed native resolution when the browser cannot verify them.

The component listens for browser resize, supported orientation changes, and visual-viewport resize events, then reads a fresh snapshot. The manual Refresh control is available when a browser delays an update.

Fullscreen enlarges the report but does not unlock additional hardware information. It can change the viewport because browser chrome and the displayed panel area change.

Detection and formatting happen locally. The Copy control writes a text report to the clipboard only after you activate it and only when the browser permits clipboard access.