MIDI Tester: Test Your MIDI Keyboard and Controller Online
This free MIDI tester shows every note, velocity value, knob turn, fader move, pedal press and pitch bend your keyboard or controller sends, live inside your browser. Plug in any device, click Connect MIDI devices, and an 88-key piano on screen lights up the moment you play.
Musicians usually open a MIDI tester when something stops working halfway through sessions, like keys that play nothing in Ableton Live, sustain pedals that never release, or knobs that FL Studio ignores. Seeing raw messages tells you whether that hardware sends correct data, which separates broken keys from DAW settings in under one minute.
How to Test a MIDI Device
Testing takes five quick steps, and you need no drivers for most modern USB keyboards and pad controllers.
- Plug in your MIDI keyboard or controller by USB, or connect older gear through any MIDI-to-USB interface.
- Open this page in Chrome, Edge, Opera or Firefox, since Safari does not support Web MIDI.
- Click Connect MIDI devices and allow access when your browser asks for permission.
- Play keys softly and firmly, then move every knob, fader, mod wheel and pitch wheel on that device.
- Press the sustain pedal several times and watch each value change in our controls panel.
What the MIDI Tester Shows
Every panel of this MIDI tester reads its own type of MIDI message, and this table explains what each one tells you.
| Panel | Value range | What it tells you |
|---|---|---|
| Keyboard | 88 keys | Which notes each device sends, with dead or stuck keys easy to spot |
| Velocity | 1 to 127 | How hard each key was struck |
| CC controls | 0 to 127 | Positions of knobs, faders, mod wheel and sustain pedal |
| Pitch bend and aftertouch | Full range | Bend wheel position and pressure on held keys |
| MIDI messages | Raw hex data | Exact bytes sent, useful for advanced troubleshooting |
Checking Velocity, Knobs, Faders and Pedals
Notes alone do not prove controllers work, because expressive controls fail more often than keys on older gear.
Velocity Response
Play one key very softly, then very hard, and velocity should climb smoothly from low numbers toward 127. Keys that always read 127 usually mean fixed velocity curves are switched on inside keyboard settings, rather than hardware faults.
Knobs, Faders and Mod Wheel
Each knob and fader sends Control Change (CC) messages with values from 0 to 127, and mod wheels normally use CC1. Turn every control slowly from end to end, because values that jump, freeze or never reach 0 or 127 point to worn or dirty potentiometers.
Sustain Pedal, Pitch Bend and Aftertouch
Sustain pedals send CC64, usually jumping between 0 and 127 as you press and release them. Pitch bend wheels should spring back to centre on their own, while aftertouch only appears on keyboards built with pressure sensors under their keys.
Testing MIDI Output With a Synth
Our MIDI tester also sends data back out, which helps when you need to check MIDI Out ports or external synths. Choose your output under Devices and press Send test note, and any connected synth from Korg, Roland, Yamaha or Arturia should play middle C. Silence usually means wrong output selection, reversed In and Out cables on 5-pin DIN gear, or synths listening on other MIDI channels.
MIDI Keyboard Not Working? Try These Fixes
When nothing shows up in our MIDI tester, these fixes solve most problems quickly.
- No device listed: Reconnect the USB cable, avoid unpowered hubs, and close any open DAW, since Windows lets only one app use some devices at a time.
- Dead or sticky keys: Keys that never light up, or never turn off, point to dirty contacts or broken key mechanisms.
- Velocity stuck at 127: Switch your keyboard back to normal velocity curves in its settings or companion software.
- Sustain works backwards: Pedals with opposite polarity read 127 at rest and 0 when pressed, so flip the switch on that pedal or change polarity in keyboard settings.
- Firefox prompt: Firefox asks for one extra site permission before it opens MIDI devices, so accept that prompt and reload.
Using Your Controller in a DAW
Passing this MIDI tester proves your hardware works, so remaining problems usually live inside DAW settings. Ableton Live lists MIDI inputs under Settings, then Link, Tempo and MIDI, where Track and Remote must be switched on for your controller. FL Studio shows controllers under Options, then MIDI settings, where each input must be enabled before it plays instruments. Logic Pro and GarageBand usually detect class-compliant keyboards automatically, so check track input settings first if notes still go missing.
How Browser MIDI Testing Works
Our page uses the Web MIDI API, the browser standard that reads MIDI messages directly from connected devices over secure HTTPS pages. Every message stays inside your browser, and nothing gets sent to our server or stored after you leave. Similar standards power our other tools, so musicians recording vocals in that same session can check their microphone with our mic test.
Frequently Asked Questions
Do I need to install drivers?
Most class-compliant USB MIDI keyboards and pad controllers work without drivers on Windows, macOS, ChromeOS and Linux. Only some older interfaces need software from their makers.
Can I test drum pads and pad controllers?
Yes, pads on Akai MPD, Novation Launchpad and Native Instruments Maschine controllers send notes and velocity like keys do. Hit each pad softly and firmly to confirm every sensor responds evenly.
Why does middle C show as note 60?
MIDI numbers every note from 0 to 127, and middle C always equals note 60. Brands label it C3 or C4 differently, which is why note names may not match printed labels on your keyboard.
Does it work with 5-pin DIN keyboards?
Yes, older keyboards with round 5-pin MIDI ports work through any MIDI-to-USB interface. Connect that keyboard’s MIDI Out to the interface’s MIDI In, then test as normal.
Can I test a MIDI keyboard on Android?
Yes, Chrome on Android supports Web MIDI with USB OTG adapters. iPhones and iPads cannot run this test, because Safari and every iOS browser lack Web MIDI support.
Does it support MIDI 2.0 devices?
Browsers read MIDI 1.0 messages, and most MIDI 2.0 controllers fall back to MIDI 1.0 automatically when connected. Notes, velocity and CC controls will still show normally.
Start Testing Your MIDI Gear
Broken keys and silent knobs waste studio time, and a MIDI tester shows exactly which part of your setup needs attention before you start recording. Connect your device, play every key and move every control, and within one minute you will know whether your hardware or your software settings need fixing. When other gear also needs checking, our hardware tester covers controllers, mice, graphics cards and microphones too.