How to Test a New Monitor: A 15-Minute Checklist
A new monitor should be verified while the return window is still open. This checklist walks through every check that matters — dead pixels, backlight bleed, uniformity, banding, motion and text sharpness — using free browser tests that take about 15 minutes in total.
Before You Start
Reset the monitor to its factory defaults first, then let it warm up for 20–30 minutes — panel behavior can shift slightly as it reaches operating temperature. Test in the room where the monitor will actually live, because ambient light changes what bleed and glow look like.
Sit at your normal viewing distance (roughly arm’s length for a desktop monitor), clean the panel gently with a microfiber cloth, and disable any browser zoom so test patterns render at native scale.
Step 1 — Dead Pixels, Stuck Pixels and Dirt
Open the Dead Pixel Test and step through full-screen White, Black, red, green and blue. On white, any dark dot is either a dead pixel, a stuck-off subpixel, or simply dirt — wipe gently before concluding it is a defect. On black, a permanently bright dot is a stuck or hot pixel; switching to pure red, green and blue tells you which subpixel is affected.
A few specks of dust look like defects but sit slightly “above” the image and move when you shift your viewing angle. Real pixel faults stay locked to the grid no matter the angle. Manufacturer warranty terms differ significantly between brands and panel grades — check the vendor’s pixel policy before buying if this matters to you.
Step 2 — Backlight Bleed and Uniformity
Dim the room, open the Backlight Bleed Test and view the full-screen black field. Light leaking from the edges or corners is backlight bleed. Some glow is normal for LCD panels, especially IPS; what matters is whether it is visible in your real viewing conditions, not just in a pitch-black stress test.
Note the difference between bleed and IPS glow: IPS glow shifts hue and intensity as you move your head, while true bleed stays fixed at the same spots. Then check the 50% Gray Screen for clouding and dirty screen effect (DSE) — large murky patches that are most visible on scrolling gray content.
Step 3 — Grayscale, Banding and Color
Run the Grayscale Test: a smooth ramp should transition without visible stripes (banding) and without a color tint toward red, green or blue. Tint across the whole panel suggests a white-point issue; tint in only some regions suggests uniformity problems.
Compare your panel against reference patches on the Color Calibration page. If you run two or more monitors side by side, the Multi-Monitor Matching patches help you align brightness and white point by eye. Full hardware calibration requires a colorimeter — browser tests verify, they do not calibrate.
Step 4 — Motion, Refresh Rate and Text
The Refresh Rate Test measures the actual update rate your browser and cable deliver — if a 144 Hz panel reports ~60 Hz, check the display settings and cable before blaming the panel. Then run the Ghosting Test: trailing smear behind the moving boxes indicates slow response, while a bright “corona” outline indicates aggressive overdrive, which you can usually reduce in the monitor’s OSD.
Finally, check readability with the Text Clarity Test and confirm the panel runs at native resolution with the Resolution Check. Blurry text on a modern display is more often a scaling mismatch (the wrong DPR or a non-native resolution) than a hardware fault.
What to Do If You Find a Defect
Document the issue: photograph the defect on the test pattern that reveals it, note the date and the monitor’s serial number, and describe under which conditions it is visible. Mild corner bleed on an IPS panel in a dark room is normal technology behavior; a cluster of dead pixels dead-center is a legitimate warranty case.
Act inside the retailer’s return window for the fastest resolution — replacement through the seller is usually simpler than a manufacturer warranty claim. Check the manufacturer’s pixel policy for your panel class, because thresholds for replacement vary by vendor.
Perguntas frequentes
How long does a full new-monitor check take?+
The core steps — dead pixels, bleed, grayscale and refresh rate — take about 15 minutes. Adding ghosting, text clarity and uniformity checks brings it to around 30 minutes. Warm the panel up for 20–30 minutes beforehand for the most representative results.
I found one dead pixel. Should I return the monitor?+
It depends on the vendor. Many manufacturers only replace panels when the number of pixel defects exceeds a threshold defined in their pixel policy, which also varies by panel grade. Retailer return windows are usually more generous than warranty terms, so decide before that window closes.
Can a stuck pixel be fixed?+
Sometimes. A stuck (colored) pixel can occasionally be revived by rapidly cycling colors over it — try the Stuck Pixel Fixer for 10–20 minutes. There is no guarantee, and a truly dead (always black) pixel is a hardware fault that software cannot repair.
Do I need to calibrate a brand-new monitor?+
For general use, the default or sRGB picture mode is fine for most panels. If you do color-critical photo or video work, hardware calibration with a colorimeter is the only accurate method — browser reference patterns help you spot a problem, not fix one.