Tool StudioYour screen resolution, viewport, and DPI, live
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Every value shows automatically, no action needed.
Resize or rotate
Watch resolution, viewport, and aspect ratio update live.
Get an exact PPI
Enter your screen's diagonal size for an accurate pixel-density number.
See your display's full resolution — with its common name (Full HD, QHD/1440p, 4K, and more) — plus aspect ratio, available screen space, browser viewport, device pixel ratio, and device type, all live. Type in your screen's diagonal size for an accurate PPI calculation, not just a rough estimate.
Three different things people often confuse: screen resolution is your whole monitor's size; browser viewport is just the visible page area, which shrinks if you resize the window; and DPI is how densely packed your screen's pixels are — a genuinely different number from an image or PDF's print DPI, and different again from a mouse's sensitivity DPI.
Everything updates live as you resize the window or rotate your device. Copy all your specs in one click for a bug report or support ticket.
Everything runs entirely in your browser — nothing is uploaded, no account needed.
Just open this page — your resolution, its common name (like Full HD or 4K), and everything else shown here is detected automatically, no clicking needed.
Screen resolution is your entire monitor's pixel dimensions, regardless of what's on screen. Available screen space is the same, minus room taken by OS taskbars/docks. Browser viewport is just the visible page area inside this browser window — it shrinks whenever you resize the window, split-screen it, or zoom in.
Check the label right under your resolution number above — it's matched automatically to common names like Full HD/1080p, QHD/1440p/2K, or 4K UHD. If nothing shows, your resolution doesn't match one of the common standard sizes closely enough to name confidently.
1080p (Full HD) is 1920×1080. 720p (HD) is 1280×720. 4K (UHD) is 3840×2160 — exactly double 1080p's width and height. 1440p (QHD/2K) sits in between at 2560×1440.
1080p — "Full HD" specifically means 1920×1080. 720p (1280×720) is just "HD," a lower resolution, often called that to distinguish it from Full HD.
No, and it's a common mix-up. 720p is 1280×720 in a 16:9 (widescreen) shape; 1024×768 is an older 4:3 (more square) shape called XGA, with fewer total pixels. They're genuinely different aspect ratios, not just different sizes.
Yes — 1280×720 divides out to exactly 16:9, the same widescreen shape as 1080p and 4K.
That's an OS display setting, not something this page can change. Windows: Settings > System > Display > Display resolution. macOS: System Settings > Displays. This page will immediately reflect whatever you set it to.
This page works the same regardless of Windows version. For the OS-native way instead: Settings > System > Display shows your current resolution directly.
This page works in mobile browsers too, and shows the same live numbers. Most phones also show resolution in Settings > Display, though the exact menu wording varies by manufacturer.
"DPI checker" gets searched for at least three different things: your screen's pixel density (what this page measures), a mouse's sensitivity setting (also called DPI, completely unrelated to your display), and an image or PDF's embedded print-resolution metadata. If you're checking a mouse's DPI, see our Mouse Tester tool — it explains why that specifically can't be reliably measured in a browser. This page is about your screen.
Not on this page — that's a file's embedded print-resolution metadata, a different thing entirely from your screen's pixel density. We don't currently have a dedicated tool for that; this page only reports your display's own resolution and pixel density.
Screens and print have genuinely different needs, not an arbitrary difference. Browsers use 96 dots per inch as their baseline — scaled up by your device pixel ratio, so a sharp Retina/HiDPI screen shows ~192 or higher, not 96 — because a screen viewed at arm's length already looks sharp at that density. Print is viewed close-up and needs far more density (300 DPI is the standard) to avoid looking blocky or soft. Neither number is wrong — they're solving different problems.
Not on this page — refresh rate (Hz) and frame rate testing is its own dedicated tool, FPS/Refresh Rate Checker, since that's a genuinely different measurement (how often your display updates per second, not how many pixels it has).
The default "Approx. DPI" is a rough estimate (96 × your device pixel ratio) — it has no way to know your screen's actual physical size, which real DPI/PPI depends on. For an accurate number, use the PPI calculator below it and enter your screen's real diagonal size in inches.
How many physical pixels on your actual screen are packed into each single CSS pixel that a website works with. A ratio of 1 is a standard-density screen; 2 or 3 means a sharp "Retina"/HiDPI display, where content looks crisper because more physical dots represent each logical pixel.
It's the width-to-height shape of your screen — 16:9 is standard widescreen, 21:9 and 32:9 are ultrawide, 16:10 and 4:3 are older or productivity-focused shapes. It matters because content designed for one shape (like a 21:9 movie) letterboxes or stretches oddly on a different one (like a 16:9 monitor).
From your browser viewport width, refined by whether touch input is detected — under 576px reads as Mobile, under 992px as Tablet (if touch-capable) or a small window (if not), under 1440px as Laptop, and above that as Desktop. It's a heuristic based on viewport size, not a certified device lookup.
Yes — the resolution, viewport, device pixel ratio, and device-type numbers are exactly what you'd check when testing how a page behaves across breakpoints or on HiDPI screens, without needing browser dev tools open.
Browser viewport and device type both react to your current window size — resizing the window, rotating your device, or changing zoom level updates them live, the same way a responsive website would. Available screen space and resolution reflect your whole monitor instead, so those stay put unless you switch monitors or your OS taskbar/dock changes.
No — every value is read locally from your own browser and device. Nothing is sent anywhere, including when you use the copy-specs button.
See your browser name and version, rendering engine, operating system, and full user-agent string, along with language, viewport, and cookie settings. Free, works entirely in your browser.
Measure your browser's live frames-per-second and get an estimate of your monitor's refresh rate. Free, works entirely in your browser.
Test if your mouse buttons, scroll wheel, and double-click all work correctly. Press left, middle, or right click and watch it register, and measure your double-click speed. Free, works entirely in your browser.
Test if every key on your keyboard works. Press any key and watch it light up on the on-screen layout — spot stuck, dead, or unresponsive keys instantly. Free, works entirely in your browser.