Significantly smaller files.
AIFF is a lossless format that prioritizes fidelity over size. Converting to MP4 introduces modern compression that typically reduces file size by an order of magnitude with no perceptible difference at normal playback or viewing.
WHY CONVERT
01
AIFF is a lossless format that prioritizes fidelity over size. Converting to MP4 introduces modern compression that typically reduces file size by an order of magnitude with no perceptible difference at normal playback or viewing.
02
MP4 is the format most receiving systems expect for this kind of content. Converting upstream avoids the rejection and silent re-encoding that often happen when AIFF reaches an unprepared pipeline.
03
MP4 files are typically smaller than their AIFF counterparts, which reduces hosting, transfer, and storage costs at scale. The savings compound when serving the same content to many recipients.
Visit this page on any modern browser — no install, no signup, no plugin.
Drag your AIFF into the drop area, or click to pick one from your device.
Conversion runs entirely in your browser. When it's done, your MP4 file downloads to your device.
QUALITY & FIDELITY
FORMAT SPECS
| AIFF | MP4 | |
|---|---|---|
| Extensions | .aiff .aif .aifc | .mp4 .m4v |
| MIME types | audio/aiff audio/x-aiff | video/mp4 |
| Introduced | 1988 | 2001 |
| Maintainer | Apple | ISO/IEC (MPEG-4) |
| Magic # | 46 4F 52 4D | 00 00 00 ?? 66 74 79 70 |
| Spec | View spec ↗ | View spec ↗ |
COMPATIBILITY
| Platform | Windows | macOS | iOS | Android | Chrome | Firefox | Safari | Edge |
|---|---|---|---|---|---|---|---|---|
| AIFF | App | Native | Native | App | — | — | Native | — |
| MP4 | Native | Native | Native | Native | Native | Native | Native | Native |
Why LocalConvert
| Category | LocalConvert | Cloud converters |
|---|---|---|
| PRIVACY | Files never leave your device. The whole pipeline runs in your browser via WebAssembly. | Files travel to a remote server, sit in queue storage, and may be retained for analytics or moderation. |
| COST | Free, no signup, no daily quotas. | Often free for small files; paid tiers for batch / large / commercial use. |
| LIMITS | Limited only by your device's memory and CPU. Uncompressed WAV stems handled comfortably on desktop. | Typical 100 MB to 1 GB per-file caps, plus rate limits. |
Apple's uncompressed PCM audio format, similar to WAV.
Typical uses
macOS audio production, sample libraries.
The most widely supported video container. Pairs efficient compression with broad device compatibility.
Typical uses
Streaming, social media uploads, recording, sharing.
Yes. LocalConvert is completely free, with no signup and no per-file or per-day limits.
No. AIFF to MP4 conversion happens entirely inside your browser using WebAssembly — your file never leaves your device.
There's no fixed cap — the practical limit is your device's available memory. Very large files may take longer or fail on low-RAM devices.
Yes — once the page has loaded, AIFF to MP4 conversion works without an internet connection. Re-open the page once to cache it.
LocalConvert uses the industry-standard tools (FFmpeg, ImageMagick, Pandoc) — quality matches what professionals use on the command line. Lossy formats will still lose some quality on each re-encode.
Last verified:
AIFF to MP4 is processed in your browser with WebAssembly. No upload, no tracking, no limits. Your file never leaves your device.