What Is a Full-Size MIDI Keyboard?
Updated Nov 11, 2026 · By 
Jonah Mercer · Editorial policy
As an Amazon Associate I earn from qualifying purchases. Buying through the Amazon links on this page costs you nothing extra. Full disclosure
A full-size MIDI keyboard is a MIDI controller whose keys are the same width as the keys on a piano. The keys send MIDI notes to a computer or other device instead of making sound on their own. Mini keys are narrower, so a full-size board suits players who want the same spacing as a piano.
What full-size keys mean
Full-size keys match the width and spacing of the keys on a piano, so your hands sit the same way they would on a piano keyboard. A full piano has 88 keys, and a MIDI keyboard may have fewer, with octave buttons shifting the range up or down. Mini keys are narrower and closer together, which changes the spacing your fingers expect. If you already play piano, a full-size board keeps the spacing familiar.
Count the keys before you choose
Key count sets how many notes you can reach without shifting octaves. The M-AUDIO Keystation 49 MK3 has 49 keys, the Novation Launchkey 49 MK4 has 49 keys, the Akai Professional MPK Mini Plus has 37 mini keys, and the Akai Professional MPK Mini IV has 25 mini keys. More keys cover a wider range at once, while fewer keys keep the board shorter. Match the count to the range you need in one stretch of playing.
Check the key action and velocity
Key action describes how the keys move under your fingers. The M-AUDIO Keystation 49 MK3 is a synth-action board, and the Novation Launchkey 49 MK4 has semi-weighted keys. Velocity-sensitive keys send a stronger or softer signal depending on how hard you press, which changes the volume of the note in your software. Try to match the action to the way you already play.
Check the connection and extra controls
A MIDI keyboard connects to a computer over USB and sends MIDI to your recording software. The M-AUDIO Keystation 49 MK3 has pitch and modulation wheels, a volume fader and a sustain pedal input. The Novation Launchkey 49 MK4 adds 16 pads, 9 faders and an OLED display, while the Akai Professional MPK Mini IV connects over USB-C and has 8 pads and 8 knobs. Pick the controls you will use, and leave out the ones you will not.
What you need
M-AUDIO Keystation 49 MK3 USB MIDI Controller
A 49-key board with full-size velocity-sensitive keys, pitch and modulation wheels, a volume fader and a sustain pedal input.
- Keys: 49
- Software named in listing: Ableton Live Lite
- USB-MIDI
- 1-year warranty stated
Akai Professional MPK Mini IV 25-Key USB-C
A 25-key controller with mini velocity-sensitive keys, 8 MPC pads, 8 knobs and USB-C for a compact setup.
- Keys: 25
- Pads: 8
- Knobs / faders: 8
- Software named in listing: Ableton Live Lite
- USB-MIDI
- 1-year warranty stated
- 2.2 lb, the lightest here
Novation Launchkey 49 MK4 USB MIDI Keyboard
A 49-key controller with semi-weighted keys, 16 pads, 9 faders, pitch and modulation wheels and an OLED display.
- Keys: 49
- Pads: 16
- Knobs / faders: 9
- Aftertouch
- Software named in listing: Ableton Live
- USB-MIDI
- 3-year warranty stated
Akai Professional MPK Mini Plus 37-Key USB
A 37-key controller with mini velocity-sensitive keys, 8 MPC pads, a 64-step sequencer and MIDI/CV/Gate I/O.
- Keys: 37
- Pads: 8
- Knobs / faders: 8
- USB-MIDI
- 1-year warranty stated
These come from our ranked list Best MIDI Keyboard, which compares them spec by spec.
Frequently asked questions
Are full-size keys the same width as piano keys?
Yes. Full-size keys match the width and spacing of piano keys, while mini keys are narrower. A full piano has 88 keys, and a MIDI keyboard with fewer keys uses octave buttons to reach the rest of the range.
How many keys do I need on a MIDI keyboard?
It depends on how much range you want at once. A 49-key board covers more notes without shifting octaves than a 25-key board, while a 25-key board takes up less desk space. The boards in the list above run from 25 to 49 keys.
What does velocity-sensitive mean on a MIDI keyboard?
Velocity-sensitive keys measure how hard you press and send that strength with the note. A hard press sends a stronger signal than a soft press, and your software turns that into a louder or quieter note. The M-AUDIO Keystation 49 MK3 and the Akai Professional MPK Mini IV both list velocity-sensitive keys.
Ranked MIDI keyboards lists
More how-to guides
Product details come from each Amazon listing and can change. Check the listing before you buy.