Mouse Button Tester
A mouse button tester checks whether each physical button on your mouse sends a correct signal to your computer. Most mice have 5–7 buttons: left click, right click, middle click (scroll wheel press), scroll up, scroll down, and two side buttons (Back and Forward). This free tool detects every button event using the browser's MouseEvent.button API — no drivers, no software, no download required.
Click, right-click, scroll, or press side buttons here
All interactions are detected instantly — no context menu pops up
Left Click
button 0
Middle Click
scroll wheel press
Right Click
button 2
Back Button
side button / button 3
Forward Button
side button / button 4
Scroll Up
wheel up
Scroll Down
wheel down
Side buttons (Back/Forward) require a mouse with extra buttons. Not all mice support button 3 or 4 — if they don't light up, your mouse may not have those buttons.
What Are the Standard Mouse Buttons?
Modern mice use the W3C MouseEvent.button standard to identify buttons. Here's what each value means and which mice support them.
| Button | Event Value |
|---|---|
| Left Click | button 0 |
| Middle Click | button 1 |
| Right Click | button 2 |
| Back Button | button 3 |
| Forward Button | button 4 |
| Scroll Up | wheel (deltaY < 0) |
| Scroll Down | wheel (deltaY > 0) |
Mouse Button Not Working? How to Fix It
If a button doesn't register on this tester, start by ruling out software issues before assuming hardware failure. First, try a different browser — some browser extensions intercept mouse events. Second, check your mouse software (Logitech G Hub, Razer Synapse, SteelSeries GG): side buttons are sometimes remapped to keyboard shortcuts at the driver level, which makes them invisible to browser event listeners. Third, test the mouse on a different computer to isolate whether the issue is hardware or software. If the button works on another machine, the problem is your driver or OS settings. If it fails everywhere, the physical switch has likely worn out — micro-switches in mouse buttons are replaceable for around $1–5 in parts if you're comfortable with basic soldering.
Mouse Click Lifespan & Double-Click Speed by Model
Mouse switches wear out over time — most gaming mice use Omron or Huano micro-switches rated for 20–100 million clicks. Double-clicking (unintended double-click on a single click) is the most common failure mode. The table below shows rated lifespans and typical failure points for popular switches.
| Switch Type | Rated Lifespan |
|---|---|
| Omron D2FC-F-7N | 10M clicks |
| Omron D2FC-F-K(50M) | 50M clicks |
| Omron D2LS (silent) | 90M clicks |
| Huano Blue Shell | 50M clicks |
| Kailh GM 8.0 | 80M clicks |
| Optical (TTC/Razer) | 100M+ clicks |
| Hall-effect (magnetic) | ∞ (no contact) |
If your left click registers as a double-click on this tester, your switch spring has likely weakened. Optical and Hall-effect switches physically cannot double-click as there is no mechanical contact that can bounce.
Frequently Asked Questions
Why isn't my right-click button being detected?
Right-click is suppressed by the browser's context menu by default. This tool disables the context menu inside the test zone, so right-click should register correctly. If it still doesn't, try clicking directly inside the dashed test area. On some touchpads, right-click may require two-finger tap or a specific corner press depending on your driver settings.
My mouse has 5 buttons but side buttons aren't showing up — why?
Side buttons (Back/Forward) send mouse events with button values 3 and 4. Some mice remap these buttons to keyboard shortcuts (Alt+Left / Alt+Right) at the driver level, which means the browser sees a keyboard event instead of a mouse event. Check your mouse software (Logitech G Hub, Razer Synapse, etc.) to ensure the side buttons are set to 'Back/Forward' rather than a custom key binding.
How do I test if my middle mouse button is working?
Press the scroll wheel down as a button (don't scroll — click it in). On this tester, the 'Middle Click' tile will flash and increment when detected. If the scroll wheel click doesn't register, it may be a hardware issue. Test it on another app: in most browsers, middle-clicking a link opens it in a new tab — if that works, the hardware is fine.
What does 'button 0, 1, 2, 3, 4' mean?
These are the values of the browser's MouseEvent.button property — a standard Web API that identifies which mouse button was pressed. Button 0 = left click, 1 = middle/scroll wheel click, 2 = right click, 3 = back (browser back button), 4 = forward (browser forward button). This tester reads these values directly to identify each button.
Can I test my mouse scroll wheel with this tool?
Yes — scroll up and scroll down are both tracked separately. Scroll your wheel inside the test zone and both 'Scroll Up' and 'Scroll Down' tiles will light up and count events. The scroll wheel press (middle click) is a separate button — click the wheel down to test that.
My mouse left click is registering multiple times per click — is that normal?
No, a single physical click should register exactly once. If you see 2–3 counts per click, your mouse may have a 'double-click' defect caused by switch wear — common in mice after 1–2 years of heavy use. This is called switch bounce or double-clicking. It can often be fixed by replacing the mouse switch, or by adjusting the double-click speed in your OS settings as a workaround.
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