MIDI vs MID: File Extension Equivalence

Compare .midi and .mid file extensions for MIDI format.

Extension Equivalence

.mid and .midi are functionally equivalent file extensions for MIDI format. Both refer to the same Musical Instrument Digital Interface standard. Files with either extension contain identical binary MIDI data. The distinction is purely nominal: .mid is the original shorter extension. .midi is sometimes used for clarity (explicit "I-D-I" in name). No technical difference exists between .mid and .midi files.

Historical Usage

.mid extension was original, established with MIDI specification in 1983. .midi extension emerged later, offering more explicit naming. Both became widely accepted. Many systems support both equally. Historical convention: .mid is more common.

Platform Conventions

Different platforms may prefer different conventions: Windows: both .mid and .midi accepted; .mid more common. Macintosh: both supported; .mid traditional. Linux: both supported equally. Web browsers: both recognized as MIDI files. Most modern systems treat both extensions identically.

File Compatibility

Renaming .mid file to .midi (or vice versa) requires only extension change; no data conversion needed. Files remain identical and fully compatible. All MIDI players, DAWs, and tools accept both extensions without issue. Interchangeability is complete.

MIME Type Designation

Both .mid and .midi files use MIME type audio/midi. Web servers and browsers detect MIME type by extension (.mid or .midi) and serve both identically. HTTP content-type header identifies both as MIDI regardless of extension used.

Naming Best Practices

For consistency and clarity: use .mid for short, economical naming. Use .midi for explicit, readable naming (especially useful for beginners learning about MIDI). Either is correct; choose based on personal or organizational preference.

File Manager Display

File managers display .mid and .midi files with identical MIDI icon/description. Neither extension has preference in file managers. Users can organize using either extension without functional consequence.

Software Implementation

Music software, DAWs, and MIDI tools recognize both extensions without special configuration. File open dialogs accept both. File save operations produce either .mid or .midi based on user choice. Implementation treats both equally.

Format Future and Standards

Both .mid and .midi will remain supported indefinitely due to MIDI ubiquity and standards recognition. Neither extension is at risk of obsolescence. Both extensions will coexist permanently in MIDI ecosystem.