Choose a screen test for the question you have.
DisplayCheck is a starting point for inspecting a monitor, laptop, tablet, or other browser-equipped screen. A single pattern cannot answer every display question. If you see one tiny dot that does not change with the picture, start with the dead pixel test. If a broad region looks darker or tinted, the uniformity test is a better match. A faint outline left by a toolbar on an OLED display calls for a brief image-retention check, not an aggressive pixel-refresh loop.
For an unfamiliar screen, the guided five-minute check leads you through a small set of observations. If you already know what you want to inspect, the complete monitor-test catalog lists every focused tool. The guided route is a workflow; the catalog is a directory; individual test pages explain one pattern and its limits.
Set up a fair visual comparison.
Clean the surface using the display maker’s instructions, let the panel warm up, and view it from your usual distance. Use its native resolution, set browser zoom to 100%, and choose a comfortable brightness. Night light, vivid modes, dynamic contrast, privacy filters, reflections, and a second display with different settings can all change what you see. Change one setting at a time and repeat the same pattern if a result looks surprising.
Fullscreen removes most surrounding interface distractions. If the browser refuses fullscreen, you can still inspect the pattern in the window; avoid judging the edges hidden by browser chrome. Look first at ordinary viewing distance, then move closer only to verify a specific spot. Decide whether the observation is also visible in the applications and lighting you actually use.
Pixels, tones, and motion need different checks.
Solid black, white, red, green, and blue fields can expose points that stay bright, dark, or the wrong color. Neutral gray is useful for larger patches, bands, or tint; a dark field may reveal LCD edge glow, but viewing angle and camera exposure can exaggerate it. Gradients can reveal abrupt tonal steps, while near-black and near-white patterns help you compare clipping across picture modes. None of those visual comparisons calculates color accuracy or contrast ratio.
The refresh-rate page estimates the cadence of browser animation callbacks. It does not directly measure how often the physical panel refreshes. Motion patterns help you compare ghosting, dark smearing, and bright overdrive halos under the same settings, but cannot report a validated millisecond response time. Use the cadence check for a browser timing question and the ghosting pattern for a visual trail question.
Know what the browser cannot certify.
Browser capability reports for HDR and wide-gamut CSS describe the active software path, not certified peak brightness or measured gamut coverage. Color appearance depends on the content, operating system, browser, profile, graphics path, and panel. An instrument and a controlled procedure are needed for objective luminance, Delta E, gamut coverage, contrast, or physical response-time results.
Keep OLED checks brief and brightness moderate. Static patterns do not repair burn-in; persistent marks should be compared again after normal varied content and against the maker’s guidance. Your visual observations stay in this browser unless you choose to copy them. DisplayCheck does not require an account or download for its core tests.
What should you do if a pattern looks wrong?
First, describe the observation without assigning a cause: “one red point on white,” “a pale lower-left corner on black,” or “a bright outline behind a moving shape.” Note the pattern, brightness, room lighting, browser, resolution, and picture mode. Then repeat the same test after changing one relevant factor. Dust, a vivid preset, a wrong refresh setting, or a color-management difference can resemble hardware trouble. A screenshot can help determine whether an artifact originates before the panel, but it cannot prove a panel is healthy; a phone photo can record location, but exposure is not a measurement.
Check whether the same issue interferes with your everyday work, games, or video. If you recently bought the display, review its return window and the maker’s current defect policy. A browser utility does not decide warranty eligibility. For a structured purchasing inspection, follow the new-monitor checklist. For help distinguishing an isolated dot from a surface mark, read how to check for dead pixels.
There is no universal pass/fail threshold for every panel and use case. Some uniformity variation is visible only on artificial fields; other issues are distracting in normal content. The purpose of these tests is to make a repeatable observation, identify the right next question, and avoid mistaking a browser report for a laboratory result.
