What Is My Screen Resolution
Detect your display's screen resolution (screen.width × height), browser viewport size, device pixel ratio (Retina/HiDPI), available area and color depth — read locally in your browser, updated live on resize, with nothing stored.
Display Details
Read locally from your device
Every value here is detected locally in your browser. Nothing is stored, logged, or sent to any server.
How to use this tool
Open the Page
On load, the tool reads your screen resolution, viewport, pixel ratio and color depth directly from your browser — no input needed.
Read the Big Number
The large value at the top is your full screen resolution (width × height); the stat grid breaks down viewport, available area, aspect ratio and color depth.
Resize to Compare
Drag the window edge or toggle full-screen and watch the viewport figure update live, while the screen resolution stays fixed. Hit Copy to grab every value at once.
If the viewport looks smaller than your resolution, that's normal — it excludes toolbars, scrollbars and the OS taskbar. A pixel ratio above 1 means you're on a Retina/HiDPI display.
Resize the window to watch this update live.
Standard density display.
Resolution vs Viewport
Screen resolution is your whole monitor. The viewport is just the area your browser renders into — smaller because of toolbars, docks, and window borders.
What Retina Means
A device pixel ratio above 1 packs multiple hardware pixels into each CSS pixel. That's why HiDPI screens look razor-sharp while reporting the same logical resolution.
What Your Screen Resolution Actually Tells You
When you ask what is my screen resolution, you're really asking how many pixels wide and tall your display is — written as width × height, like 1920 × 1080. This checker reads that value straight from your device the moment the page loads and shows it as the large number at the top. It mirrors whatever your operating system is currently set to, so if you've changed your display scaling or plugged into an external monitor, the figure reflects that exact setup rather than the panel's theoretical maximum.
Knowing your resolution is useful for more than curiosity. Designers use it to test how layouts behave on a real screen, support agents ask for it when diagnosing display problems, gamers check it before changing in-game settings, and anyone buying a monitor wants to confirm what they're already running. Because the tool reads live values, it's also a quick sanity check after you change a setting.
Resolution, Viewport, and Why They Differ
The single biggest point of confusion is the gap between screen resolution and browser viewport. They sound like the same thing, but they measure different areas:
- Screen resolution (
screen.width × screen.height) is your entire physical display — every pixel the monitor can show. - Viewport size (
window.innerWidth × innerHeight) is only the rectangle your web page is rendered into. It's always smaller because it excludes the address bar, tabs, scrollbars, and any operating-system taskbar or dock. It also shrinks the moment you un-maximize the window.
This tool measures the viewport live: it attaches a resize listener, so dragging the window edge or toggling full-screen updates that number instantly while the resolution stays put. There's also available size (availWidth × availHeight), which is the resolution minus space permanently reserved by the OS for things like the taskbar — a middle ground between the two.
Device Pixel Ratio and Retina Displays
The third value worth understanding is device pixel ratio (DPR), read from window.devicePixelRatio. It tells you how many physical hardware pixels are packed into a single CSS pixel. A traditional monitor has a DPR of 1. Apple's Retina screens and most modern HiDPI laptops and phones report 2 or even 3.
This is why a phone might report a logical resolution of 390 × 844 yet render text with stunning sharpness — under the hood it's pushing two or three times that many real pixels. When DPR is above 1, this checker also shows the calculated physical pixel count so you can see the full hardware density behind the logical number. For web developers, DPR is critical: it decides whether you need @2x images and how a canvas should be scaled to avoid blur.
Color Depth: How Many Colors Your Screen Shows
Finally, color depth (screen.colorDepth) reports the bits used per pixel for color. A standard 24-bit value means about 16.7 million colors. A higher reading points to a wide-gamut or HDR-capable display.
Detected Locally, Stored Nowhere
Every figure on this page is read with standard browser APIs that run entirely on your machine — nothing is uploaded, logged, or saved. You could even go offline and it would still work once loaded. If you're building or debugging web layouts, pair this with the JSON Formatter for inspecting config, or the Base64 Encode / Decode tool for working with embedded image data.