ScreenTest.Pro

Screen resolution checker

Your screen's resolution, scaling, aspect ratio and pixel density — read live from this device, with the difference between reported and physical pixels made explicit.

This screen

live
px
Physical pixels
Browser viewport
Pixel ratio
Aspect ratio
Orientation
Color depth
Refresh rate

Reported vs physical pixels

Two honest numbers describe every modern screen. The reported resolution is what the OS tells software after scaling — the coordinate space your windows live in. The physical resolution is how many pixels the panel actually has. A MacBook that "looks like" 1512×982 is physically 3024×1964; a phone reporting 384×832 may pack 1080×2340. The ratio between them is the pixel ratio above, and it's why screenshots come out bigger than your screen "is".

Neither number is a lie — they answer different questions. Buying advice and spec sheets talk physical; CSS, game HUDs and "why is this text so small" talk reported.

Common resolutions

NamePixelsWhere you meet it
720p (HD)1280 × 720budget TVs, streaming tiers
1080p (Full HD)1920 × 1080the desktop default for a decade
1440p (QHD)2560 × 1440the gaming-monitor sweet spot
4K (UHD)3840 × 2160TVs, creator monitors
5K5120 × 288027-inch “Retina-class” displays
8K7680 × 4320flagship TVs; content is scarce

Phones mostly run tall 19.5:9 to 20:9 panels at "1080p-class" widths; ultrawide monitors stretch to 21:9 and 32:9. The aspect-ratio row above names yours if it's one of the usual suspects, and shows the exact reduced ratio either way.

Density: where sharpness actually comes from

Resolution alone says nothing about sharpness — 1920×1080 is crisp on a 13-inch laptop and coarse on a 27-inch monitor. Pixels per inch is the number that tracks what you see. Type your screen's diagonal size into the panel above and it computes PPI from the physical pixel count; the long version, with viewing-distance math, is in Screen resolution, PPI and pixel density explained.

Once you know what the panel is being fed, it's worth checking what it does with it: the dead pixel test takes two minutes, the refresh rate test verifies the panel's speed, and the benchmark scores how fast this device actually pushes those pixels.

FAQ

resolution, scaling and densityall articles →

What is my screen resolution?

The big number above — that’s what your operating system reports for this screen, in the pixels websites and apps lay out against. If you’re on a scaled display (most laptops and every phone), the panel physically has more pixels than that; the “physical pixels” row shows the native count.

Why does my 4K monitor report 1920×1080?

Display scaling. At 200% scaling, the OS maps four physical pixels to one logical one, so a 3840×2160 panel reports 1920×1080 — everything is normal, and text is sharper for it. The pixel-ratio row above shows the factor. You’re only actually running at 1080p if the physical-pixels row also reads 1920×1080.

What’s the difference between resolution and viewport?

Resolution is the whole screen; the viewport is the part your browser window currently covers, minus its own chrome. Resize the window and watch the viewport row follow. Web designers care about viewports; monitor shoppers care about resolution.

Is higher PPI always better?

Higher pixel density means sharper text and images — up to the point where your eyes can’t resolve the difference at your viewing distance. A 27-inch 4K monitor at arm’s length (~163 PPI) already sits near that limit for most people; a phone at 460 PPI is comfortably past it. Past that, more pixels cost GPU performance and battery for detail nobody sees. The deeper dive is in Screen resolution, PPI and pixel density explained.

How do I change my screen resolution?

On Windows: Settings → System → Display → Display resolution — and set scaling on the same page. On macOS: System Settings → Displays, where the choices are presented as “looks like” sizes. Run the panel at its native resolution and use scaling for size; a non-native resolution makes everything slightly blurry because the panel has to interpolate.