Double-Click Test — Is Your Mouse Chattering?.
A worn mouse switch fires twice when you meant to click once. Click the pad the way you normally would and this test times the gap between clicks in milliseconds — anything under about 80 ms is a double-click your hand didn't make. It counts every one so you can prove the fault.
Click to begin
Single-click the pad, normally
Online double-click test.
Each number is the time since your previous click. Real single clicks are 100 ms+ apart; a chattering switch double-fires in under 80.
How to run a clean chatter test
- Click the way you normally doDon't force slow, deliberate clicks — chatter shows up during natural use. Single-click at your usual speed and let the timer catch any double-fires.
- Test one button at a timeThis measures the gap between consecutive clicks regardless of button. Use only the button you're checking so a fast left-then-right doesn't read as chatter.
- Do at least 20–30 clicksA healthy switch might fluke a close gap once. A genuinely worn switch chatters repeatedly — a rising chatter count over many clicks is the real signal.
- Leave a full second between clicksSpace your intended clicks out. Any gap that then comes back under 80 ms is the switch firing on its own, not you clicking fast.
How to use the double-click test
- 1Pick a threshold. 80 ms is a good default. Lower it to 50 ms to catch only the most obvious double-fires, or raise it to 100 ms to be stricter.
- 2Single-click the pad. Click once, wait about a second, click again. The big number shows the gap in milliseconds since your last click, and turns red when it drops below the threshold.
- 3Watch the chatter count. Every sub-threshold gap adds to the Chatter events tally and drops a red bar into the recent-gaps strip. One or two might be noise; a steady stream means a failing switch.
- 4Confirm and act. If the verdict reads "Chatter detected," your switch is likely worn. Check the mouse test to see the extra events land, then look at warranty, firmware debounce, or a switch replacement.
How the double-click test works
Every time you press a mouse button, the browser fires a mousedown event with a high-resolution timestamp. This test simply subtracts each timestamp from the one before it to get the inter-click interval in milliseconds. When you single-click normally, those intervals are hundreds of milliseconds apart. When a switch chatters, the metal contacts bounce and send a second press just a few milliseconds after the first — far faster than a human finger can move.
The threshold draws the line. A deliberate double-click, the kind that opens a file, lands anywhere from roughly 100 ms up to your operating system's double-click speed limit (often around 500 ms). A chatter double-click is different: the two presses arrive within 10–50 ms, which no hand produces. Flagging gaps under about 80 ms catches the faults while leaving your real clicks alone.
Chatter happens because the tiny metal leaf inside a mechanical switch loses tension or oxidises with age, so it "bounces" on contact instead of making one clean connection. Mice fight this with debounce — a firmware delay that ignores presses too close together — but once a switch degrades past the debounce window, the extra clicks leak through. That's what you're measuring here.
When to run a double-click test
Files open on one click
If single-clicks keep launching files or opening links, your left switch is almost certainly double-firing. This test proves it in seconds.
Drag-and-drop drops early
A chattering button releases mid-drag, so items you're moving get dropped or deselected. The gap timing confirms the cause.
Losing item stacks in games
One click splitting or moving a whole stack twice is classic chatter — annoying in inventories and fatal in fast games.
Checking a warranty claim
A repeatable chatter count with millisecond gaps is exactly the evidence a manufacturer wants before replacing a mouse.
After a repair or switch swap
Replaced the switches or applied contact cleaner? Re-run to confirm the double-fires are actually gone.
Vetting a used mouse
Worn switches are the most common fault in second-hand mice. Thirty clicks here tells you before you commit.
Double-click test glossary
- Chatter
- Unintended repeat clicks from a worn switch — one physical press registering as two or more, milliseconds apart.
- Debounce
- A firmware delay that ignores a second press arriving too soon after the first, filtering switch bounce. It fails once a switch degrades.
- Inter-click interval
- The time between two consecutive clicks. This test reports it in milliseconds; sub-80 ms values suggest chatter.
- Double-click speed
- The OS setting for how close two clicks must be to count as a deliberate double-click — typically up to about 500 ms.
- Mechanical switch
- The clicky component under each button (Omron and clones are common). Its metal contacts wear out over millions of clicks.
- Bounce
- The physical vibration of switch contacts on impact, which can briefly break and remake the connection — the root cause of chatter.
Frequently asked questions
How do I know if my mouse is double-clicking?
Single-click the pad above at your normal speed, spacing your clicks about a second apart. If the tool logs gaps under 80 ms — clicks you didn't consciously make — and the Chatter events count climbs, your switch is double-firing. A healthy mouse shows only the large gaps that match your actual clicking, and a verdict of "No chatter detected."
What gap counts as chatter versus a real double-click?
A deliberate double-click, like opening a file, usually lands between about 100 ms and your OS double-click limit (often ~500 ms). Switch chatter is much faster: the bounced second press arrives within roughly 10–50 ms, quicker than any human can click. That's why the default 80 ms threshold reliably separates a hardware fault from normal fast clicking.
Can I fix a double-clicking mouse myself?
Sometimes. Options, roughly easiest first: increase the debounce time in your mouse's software if it exposes that setting; blow out or apply contact cleaner to the switch; or, for a permanent fix, replace the mechanical switch (a few dollars, but it requires soldering). If the mouse is under warranty, a repeatable chatter count from this test is strong evidence for a free replacement.
Why does my brand-new mouse show occasional close gaps?
An isolated sub-threshold gap now and then isn't necessarily a fault — it can be you genuinely clicking fast, or a stray bounce the firmware nearly caught. Chatter is defined by repetition: a worn switch produces double-fires again and again across a session. If a new mouse only flags once in fifty clicks, it's almost certainly fine.
Does the browser or my polling rate affect the gap timing?
The timing uses a high-resolution clock accurate to well under a millisecond, so it's plenty precise for chatter, which happens on a scale of tens of milliseconds. Polling rate adds at most a 1–8 ms sampling delay, which won't turn a real click into a false chatter reading. If you want to check your report rate separately, use the polling rate test.
Is this the same as the OS double-click speed setting?
No. Your operating system's double-click speed decides how close two clicks must be to trigger a double-click action, and you set it for comfort. This test measures a hardware fault: a switch sending two electrical pulses from one press. Changing your OS setting won't stop a chattering switch — it only changes how the OS interprets clicks.