.midi

What is a .midi file?

MIDI files contain musical instructions, not audio — note data, timing, and velocity that any synthesiser can play back.

Safe format
Type Audio
By MIDI Manufacturers Association
MIME audio/midi

Drop any file to identify it

No upload. No signup. No sending your file halfway across the internet.
We tell you what it is, right here in your browser.

What is it

You have a MIDI file — but it's not an audio recording. MIDI contains musical instructions: which notes to play, when to play them, how hard to press, which channel, which program change. Think of it as sheet music for computers. A MIDI file of Beethoven's 5th is under 50 KB. The same piece as WAV would be 300 MB.

MIDI (Musical Instrument Digital Interface) was standardised in 1983 so that synthesizers from different manufacturers could talk to each other. The protocol hasn't fundamentally changed since — a testament to getting the design right the first time. MIDI 2.0 arrived in 2020 with higher resolution, but the original spec still powers music production, live performance, DJ controllers, lighting rigs, and video game scores worldwide.

Every OS plays MIDI through built-in synthesizers (the quality varies wildly). GarageBand, Logic, Ableton, FL Studio, and every DAW imports MIDI for editing and re-instrumentation. For better playback quality, load the MIDI into a DAW and assign proper virtual instruments. The magic of MIDI is that you can change the tempo, key, and instrumentation without affecting quality — because there's no audio to degrade.

Technical details
Full Name
Musical Instrument Digital Interface
MIME Type
audio/midi
Developer
MIDI Manufacturers Association
Magic Bytes
4D 54 68 64
Safety
.midi is a known, safe format.
What opens it
Every OS (built-in playback)
FREE All
GarageBand
FREE macOS / iOS
Any DAW
PAID All
FAQ
Is MIDI the same as audio?
No. MIDI contains performance data (notes, timing, velocity), not sound. It's like sheet music versus a recording. MIDI needs a synthesizer to produce audio — the sound depends entirely on which instruments are assigned.
Can I convert MIDI to MP3?
Yes, but you need to render it first. Open the MIDI file in a DAW (GarageBand, FL Studio, or the free LMMS), assign instruments, then export as MP3 or WAV. The result depends on which virtual instruments you use.
Why are MIDI files so small?
MIDI stores instructions (play note C4 at velocity 80 for 500ms), not audio waveforms. A three-minute song might be 30 KB as MIDI versus 30 MB as WAV. It's the difference between a recipe and a meal.
Related formats