Gamepad tester not detecting your controller

Most of the time a controller that does not show up in a browser test is not broken. Web pages only see a gamepad after you press a button, and the operating system has to recognise it first. Work through the checks below in order, and test again after each one so you know which step fixed it.

Step 1: press a button on the page

Browsers hide connected gamepads from a page until you interact with the controller while the page is open. This is a privacy rule, not a fault: a website cannot list your devices on its own.

Open the gamepad tester and click once inside the page so the tab has focus.
Press a face button (A, Cross) or move a stick. Pressing only the Home, PS or Xbox button often does not count, because the system keeps it for itself.
If the controller appears, the problem is solved: nothing was wrong.

If nothing appears, leave the tab open and continue. Keep the test page in the foreground: many browsers stop sending gamepad data to background tabs and minimised windows.

Step 2: check that the operating system sees the controller

The browser can only read what the operating system has already recognised. Check that first, outside the browser.

Windows: open Settings, then Bluetooth & devices, and see whether the controller is listed and connected. The classic Set up USB game controllers panel (search for joy.cpl) shows whether Windows reads its buttons.
macOS: open System Settings, then Bluetooth, and check that the controller is connected. Newer versions also list game controllers in their own settings page.
Android and ChromeOS: check the Bluetooth settings and that the controller is listed as connected, not only paired.

If the system does not see the controller, the browser never will. Fix the connection first (step 3).

Step 3: fix the connection

Try a cable. Use a data cable, not a charge-only one, plugged straight into the computer rather than a hub. A controller that works by cable but not by Bluetooth points to pairing or Bluetooth, not to the controller.
Re-pair over Bluetooth. Remove the controller from the Bluetooth list, put it into pairing mode again (the method differs by model, check the maker's instructions) and pair it fresh.
Charge it. A nearly flat battery can connect and then drop out after a few seconds.
Disconnect it from other devices. A controller paired with a console nearby may reconnect to the console instead of the computer.
Try another port or computer. If it is detected nowhere, by cable or Bluetooth, the controller or its cable is the likely cause.

Step 4: check the browser and other apps

Close apps that take over the controller. Steam with Steam Input, DS4Windows, remapping tools and some game launchers can grab the controller or present it as a different virtual device. Close them completely, including the tray icon, and test again.
Use an up-to-date browser. Chrome, Edge, Firefox and Safari all support web gamepads in current versions, but which controllers they recognise depends on the browser and the operating system.
Try a second browser. If the controller works in one browser and not another, the controller is fine; the difference is in how that browser and system handle it.
Restart the browser after plugging in, especially if the controller was connected while the browser was already running.

Detected, but the buttons are wrong

When the browser recognises a controller it reports it with the standard layout, and buttons appear in the usual places. When it does not recognise the model, it passes the raw button and axis numbers in whatever order the controller sends them. Then a button may light up in the wrong place, or the triggers may show up as axes.

This is a mapping difference, not a hardware fault. Look at which raw button or axis number reacts, not where it is drawn.
Remapping tools and Steam Input can also swap buttons. Close them and test again.
If the same button never reacts at all, under any mapping and in any browser, that points to the button itself. Check it with the gamepad tester and in a game.

Detected, but vibration does not work

Rumble from a web page needs the browser to support it for that controller. Chromium-based browsers such as Chrome and Edge support it for many common controllers; support in other browsers varies, and some controllers do not expose rumble to pages at all. Before you suspect the motors:

Run the controller vibration test in Chrome or Edge with the controller connected by cable.
Check that vibration is not switched off in the controller settings of your system or in Steam.
If rumble works in a game but not in the browser, the motors are fine.

Once it is detected: what to test next

Run the full gamepad tester for buttons, triggers and sticks. For a specific model use the PS5 controller test, the Xbox controller test or the Joy-Con drift test. If a stick moves on its own, read controller moving by itself and measure it with the stick drift test.

A browser test reads the controller; it cannot pair it, update its firmware or repair it. Those steps happen in the operating system, the console or the maker's app.

Questions

Why does the gamepad tester say “press a button”?

Browsers only reveal a gamepad to a page after you press a button or move a stick while the page is open. Click into the page and press a face button, not only the Home button.

My controller works in games but not in the browser. Is it broken?

No. Games often use their own drivers or Steam Input, while the browser relies on the operating system. Close Steam and remapping tools, try a cable and another browser, and test again.

Does the gamepad tester work over Bluetooth?

Yes, if the operating system has paired and connected the controller. The page cannot pair it for you; pair it in the Bluetooth settings first, then press a button on the page.

Why are my buttons shown in the wrong place?

The browser did not recognise the model and passed the raw button numbers. Each button still reports; only the drawing is off. Check which number reacts when you press it.