Which test for which symptom
If you know what is wrong but not which test to open, start here. Every row links to the test that answers the question, and to the guide that explains what to do with the answer.
| Symptom | Test | What a result tells you |
|---|---|---|
| A key does nothing, or types the wrong character | Keyboard Test | Whether the press reaches the browser at all, which separates a dead switch from a layout or software problem |
| You need the exact event values for a keyboard shortcut | Key Code Viewer | What your browser reports for that physical key right now, which no specification can tell you |
| One click registers as two | Mouse Test | The gap between the two clicks: a few milliseconds is switch chatter, a few hundred is your hand |
| The trackpad ignores gestures | Touchpad Test | Whether movement, clicks and gestures arrive separately, which points at the driver rather than the pad |
| The controller moves on its own | Gamepad Test | The resting value of each stick axis, which is what stick drift actually is |
| Nobody can hear you on a call | Microphone Test | Whether any signal reaches the browser, which rules the meeting application in or out in one step |
| The camera shows a black picture | Webcam Test | Whether the camera opened and at what resolution, which separates a shutter from a driver problem |
| Sound only comes from one side | Speaker Test | Which channel is silent under a tone rather than under music, which is the only fair test |
| There is a dot on the screen that will not go away | Dead Pixel Test | Whether it is dust, a dead pixel or a stuck pixel, which decides whether a warranty claim is worth filing |
| The picture looks banded, blotchy or soft | Monitor Test | Which pattern the fault shows up in, which narrows it to banding, uniformity, scaling or overdrive |
| You need to know what your display is actually running at | Screen Info | Resolution, viewport, device pixel ratio and an estimated refresh rate, with the estimate labelled as one |
Compiled by MyGearCheck. Every entry in the last column is bounded on purpose: these tests observe what reaches the browser, which is enough to separate hardware from software and not enough to name a component.
Guides that go with the tests
A test tells you what is happening. These explain what to do about it, and each one links back to the test it belongs with.
Keyboard key not working: how to tell hardware from software
A key that does nothing is either a dead switch or something intercepting it. Four checks separate the two in about two minutes, starting in your browser.
Controller stick drift: how to test for it and what to do next
An analog stick drifts when it reports movement while you are not touching it. Test it in your browser in thirty seconds, then decide between a fix, a warranty claim and a replacement.
Mouse double-click chatter: what causes it and how to fix it
One click registering as two is switch chatter. Confirm it in your browser, rule out the settings that imitate it, and work through the fixes in order of cost.
N-key rollover and ghosting explained, with a test you can run now
Rollover is how many keys your keyboard can report at once. Ghosting is a key you never pressed. Here is the difference, and what a browser test can and cannot prove about either.
Microphone not working in Windows 11: a step-by-step check
Start in the browser, because it tells you in ten seconds whether the microphone reaches your system at all. Then work outward through permissions, device selection and drivers.
Webcam shows a black screen: browser, driver and privacy-shutter checks
A black webcam preview has four common causes and they are quick to separate. Start with the physical shutter, because it is the most embarrassing one to miss.
Dead pixel warranty: what is actually covered
Most warranties do not replace a screen for one dead pixel. Here is the standard the thresholds come from, how to find the policy for your model, and what evidence a claim needs.
How to check a second-hand laptop before you buy it
A fifteen-minute checklist you can run from the seller's own browser, covering the keyboard, trackpad, screen, camera, microphone and speakers, with what each result actually proves.
How to check a used monitor before you buy it
Six patterns, ten minutes, and a dark room. What each one reveals, what counts as normal, and which faults are worth walking away from.
Only one speaker works: how to diagnose left, right and balance problems
Test each channel separately before you suspect the hardware. A balance setting, a half-inserted jack and a mono source all produce the same symptom.
event.key vs event.code vs keyCode: which one should you use
Use event.key for what the user typed and event.code for where the key physically is. keyCode is deprecated and its values are inconsistent. Here is how to choose, with a full reference table.
Laptop touchpad not working: eight checks before you call support
Start with the disable shortcut, because it is the answer more often than anything else. Then work through gestures, drivers and the one reading that confuses everybody.