Preparation before connection
- Check the USB cable and device power
- If the DAW or editor is occupying a MIDI port, close it once.
- Select the display closest to the actual machine from 25 keys, 49 keys, 61 keys, or 88 keys
- Grant browser MIDI permissions only to the target site
Input
- Start a MIDI connection and select the target input device.
- Press each key from low to high, and check the on-screen keyboard and note numbers.
- Press softly and firmly to see if the velocity value changes.
- Try the sustain pedal or pressing multiple keys at the same time and check the event history.
isolate symptoms
| Symptom | What to Check |
|---|---|
| Device is not displayed | Power, USB, browser permissions, or use by another app |
| Only specific keys do not respond | Note number and note on/off status |
| Constant strength | Velocity value and keyboard settings |
| the sound continues to grow | Note off and sustain pedal values |
This test only checks MIDI input and does not check audio output or sound source plug-in operation.
Specific example: When only a specific key does not respond
Press one key at a time from low to high, and check the keyboard position, note name, and note number on screen. Press with different strengths and also check that velocity is not fixed near 0 or at the maximum.
If only the same physical key does not respond even with another USB port or MIDI channel, the device contacts or settings may be at fault. If no keys respond, first check permissions, connection, and browser support.
- Connect your MIDI device and open the page in a compatible browser.
- Allow MIDI access and select your input device.
- Press all the keys in sequence to check the note number and velocity.
- Check pedals, channels, multiple hits, simultaneous presses, and compare event history.
Web MIDI API may not be available depending on the browser or connection method. If your device does not appear in the list, please check the compatible environment and USB connection.
Frequently asked questions
- Can you make sounds by pressing the keyboard on the screen with the mouse?
- The on-screen keyboard is used to check the MIDI input and display the reception status. Please press the keyboard of the actual device to confirm.
- Is it a malfunction if there is no sound when I press the keyboard?
- MIDI is performance information, and the device or tester itself may not have a sound source. Check if the input event is displayed.
Try It in Your Browser
Your input is processed entirely in your browser. Keep the original data, review the output, and only then save or share it.
Open MIDI keyboard input tester