MIDI Tester for PC and browser troubleshooting
Connect a MIDI device, grant browser permission, and verify that note, control-change, and device status messages arrive as expected. Connect the device, press a control, and compare the live values with the physical response. Results depend on browser support, operating-system mapping, firmware, and the USB or wireless connection path.
How to test a MIDI keyboard or pad controller online
Connect and power the MIDI device before requesting access. Approve the browser prompt, confirm that the input name appears, then play keys or pads at different strengths. Move knobs, faders, wheels, and pedals one at a time while watching the three-byte event log update.
- Test low and high velocity notes
- Move continuous controls through their full range
- Release keys to confirm note-off messages arrive
Read MIDI note, velocity, and control-change messages
The first byte identifies the message type and channel, the second commonly identifies a note or controller number, and the third commonly carries velocity or a control value. This compact log is designed to confirm that messages arrive, not to replace a full protocol monitor or digital audio workstation.
Fix a MIDI controller not detected by Web MIDI
Check power, USB connection, driver installation, and whether another application has exclusive access to the device. Reload after connecting, then try Chrome or Edge on a secure HTTPS page. Safari and some privacy-focused browser configurations may not expose Web MIDI even when the device works in music software.
MIDI tester privacy and browser compatibility
Permission is requested only after you select the button. Device names and incoming messages are processed in the current browser session and are not uploaded by this tool. Web MIDI support and permission behavior vary by browser, operating system, and enterprise security policy.