Screen Test

Everything your browser can tell about your display — resolution, refresh rate, pixel density and color — detected the moment the page loads. Nothing to install, and nothing leaves your device.

Your screen resolution is

 

Browser viewport

The space a website actually gets inside your browser window — updates live as you resize.

Pixel density

 

Refresh rate

Quick estimate from animation frame timing.

Color

 

Orientation

Updates the moment you rotate your device.

Touchscreen

 

How to Check Your Screen Online

Open this page and the numbers above are already yours — the browser reads them straight from your display, with no permission prompts and nothing sent anywhere. Here is what each of them means.

Screen resolution

Resolution is the number of tiny dots — pixels — your display lights up to draw the picture: 1920 × 1080 is Full HD, 3840 × 2160 is 4K. Because your system scales everything up to keep text readable, the browser often works with a smaller number; this page multiplies it back to show the panel's true figure. If it still looks lower than the box promised, display scaling or browser zoom is almost always the reason.

Pixel density

Pixel density is how many of the screen's real pixels are used to draw each dot of the picture. A value of 2× or higher is what Apple calls Retina and everyone else calls HiDPI — text looks noticeably sharper. In-between values like 1.25× or 1.5× usually come from display scaling in Windows, which makes everything comfortably bigger. It is also the reason a 4K laptop can honestly report a resolution of 1920 × 1080.

Browser viewport

The viewport is the part of the browser window a web page can actually draw into — the screen minus toolbars, taskbars and any neighboring windows. Web developers design against this figure rather than the screen itself, which is why it updates live as you resize the window.

Refresh rate

Refresh rate is how many times per second the display redraws, measured in hertz. 60 Hz is the long-standing standard, while 120 Hz and above makes scrolling and games visibly smoother. The figure above is a quick estimate from animation timing; the dedicated refresh rate test measures it precisely and can catch a high-refresh panel being held at 60 Hz.

Color depth, gamut and HDR

Color depth is the number of bits used per pixel — 24-bit means about 16.7 million colors, and 30-bit panels step up to over a billion for smoother gradients. The gamut is the range of colors the display can show: sRGB is the web's baseline, while Display P3 or Rec. 2020 mean a wide-gamut screen. HDR support is detected separately and unlocks brighter highlights in supported videos and games.

Orientation

Orientation is simply whether the screen is currently wider than it is tall. On phones and tablets it flips live as you rotate the device; on a desktop it changes when a monitor is set to portrait in the display settings — a favorite of programmers and anyone who reads long documents.

Touch support

The browser reports whether your screen accepts touch and how many fingers it can track at once — most touchscreens handle ten. A report of zero on a touch laptop usually means the digitizer's driver is disabled or the browser is ignoring it.

Check for dead pixels
Fill the screen with solid colors to spot dead, stuck or hot pixels — takes under a minute.
Start the check
Measure refresh rate
Time real rendered frames to find the exact Hz your browser sustains — and catch a 120 Hz display stuck at 60.
Measure now

Frequently asked questions

Because your operating system runs display scaling. At 200% scaling, Windows and macOS tell apps the screen is 1920 × 1080 so that text stays a comfortable size, while the panel still lights up its full 3840 × 2160. This page multiplies the reported size by your pixel density to recover the real number, so the headline figure should match the panel. If it does not, check for browser zoom — it changes the numbers too.
Compare the headline figure with the common standards: 1280 × 720 is HD, 1920 × 1080 Full HD, 2560 × 1440 QHD, 3840 × 2160 4K UHD and 7680 × 4320 8K. Ultrawide monitors use their own set, such as 2560 × 1080 and 3440 × 1440. The aspect ratio shown under the headline tells you whether the panel is a regular 16:9, a productivity 16:10 or an ultrawide 21:9.
Usually because something is deliberately holding it down. Phones drop to 60 Hz to save battery, laptops do the same on power-saver profiles, and on desktops the display settings may still be set to 60 Hz even though the panel can do more. The cable can also be the cap — older HDMI versions cannot carry 4K above 60 Hz. Set the rate explicitly in your display settings, then verify with the refresh rate test.
No. For privacy reasons the browser only exposes numbers — size, density, color capabilities and refresh timing. It cannot read the monitor's model name, serial number or any other identifying details, and neither can this page. Anything that claims to name your exact monitor from inside a web page is guessing from those same numbers.
Pixel density is how many real pixels the screen uses for each dot of the picture. Whole numbers like 2× come from HiDPI and Retina displays. In-between values almost always mean Windows display scaling: 125% shows up as 1.25×, 150% as 1.5×. Browser zoom changes the value too, which is why it moves when you press Ctrl and + or −.
Browser zoom makes every dot of the page bigger or smaller, and the measurements on this page scale along with it. Zooming in makes the reported resolution drop and the pixel density rise, while the physical panel obviously never changes. For accurate readings reset zoom to 100% — Ctrl+0 on Windows and Linux, Cmd+0 on a Mac.
Use the dead pixel check linked above. It fills the screen with solid red, green, blue, white and black, one after another, so a pixel that is stuck on one color or permanently dark stands out immediately. Clean the screen first — a speck of dust is the most common false alarm — and give each color a few seconds of close attention.
Yes to both. Every value on this page is read locally by your browser and never sent to a server — there is nothing to install, no account, and no way for anyone to see your results. The page simply shows you what your own browser already knows about the display it is running on.