Extract Audio from MOV to CAF — Free Online Tool
Extract audio from MOV video files and save it as CAF (Core Audio Format) — Apple's professional audio container that overcomes the file size limitations of AIFF and WAV. The audio is converted to uncompressed PCM (16-bit signed little-endian), making CAF ideal for use in Logic Pro, GarageBand, and other Apple audio workflows that require lossless fidelity.
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FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
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Note: Browser-based encoding uses approximate quality targets. For precise CRF compression, copy the FFmpeg command above and run it on your desktop.
Estimated output:
Conversion Complete!
DownloadHow It Works
MOV files typically store audio as AAC or other compressed codecs alongside a video stream. This tool strips the video entirely and decodes the audio, then re-encodes it as PCM 16-bit signed little-endian (pcm_s16le) inside a CAF container. Unlike a simple remux, this is a full audio transcode — the original compressed audio is decoded to raw PCM samples, giving you uncompressed audio suitable for professional editing. The CAF container itself supports files larger than 4GB (unlike WAV), making it a practical choice for long recordings extracted from MOV sources. The video stream is discarded with the -vn flag and no video data is written to the output.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg binary — the open-source multimedia processing engine that this browser tool runs as a WebAssembly (FFmpeg.wasm) module. On the desktop, this assumes FFmpeg is installed and available in your system PATH. |
-i input.mov
|
Specifies the input file as a MOV (QuickTime) container. FFmpeg reads all streams — video, audio, and any subtitle or chapter data — from this file before the output flags determine what gets written. |
-vn
|
Disables video output entirely, telling FFmpeg to ignore all video streams from the MOV. Since CAF is a pure audio container, this flag ensures no attempt is made to write video data, and the output file contains only the decoded audio. |
-c:a pcm_s16le
|
Transcodes the audio stream to PCM 16-bit signed little-endian — uncompressed audio at CD quality bit depth. This decodes whatever compressed audio codec was in the MOV (typically AAC) into raw PCM samples, which CAF stores natively and Apple's CoreAudio reads without any decoding step. |
-b:a 128k
|
Sets a target audio bitrate of 128 kbps. For PCM output this parameter is effectively inert — uncompressed PCM bitrate is fixed by sample rate and bit depth — but the flag is passed as part of the standard command template and is harmlessly ignored by FFmpeg in this context. |
output.caf
|
Defines the output filename and signals to FFmpeg that the container format should be CAF (Core Audio Format). FFmpeg infers the CAF muxer from the .caf file extension and writes the pcm_s16le audio stream into this Apple-native audio container. |
Common Use Cases
- Extracting a field recording or location audio track from a MOV file shot on an iPhone or DSLR, to import as a clean PCM audio file into Logic Pro or GarageBand for mixing
- Pulling the audio from a Final Cut Pro export (MOV) to create a standalone CAF audio asset for use in an iOS or macOS app via AVFoundation
- Converting MOV-wrapped interview footage audio to uncompressed PCM CAF for archival, preserving full fidelity without the file size constraints of the WAV format
- Extracting dialogue or voiceover audio from a QuickTime MOV file to deliver to a sound editor who requires uncompressed CAF files for post-production in an Apple-native workflow
- Stripping the audio from a screencasting MOV to produce a high-quality CAF track for synchronization with a separately edited video timeline in Final Cut Pro
- Decoding AAC-compressed audio stored in a MOV file to uncompressed PCM inside CAF so that audio processing software can work on raw samples without lossy codec artifacts
Frequently Asked Questions
The conversion from AAC (lossy) to PCM (lossless) does not introduce additional quality loss beyond what already occurred when the MOV's AAC audio was originally encoded. PCM is uncompressed, so the decoded AAC samples are stored exactly as decoded — no second-generation compression is applied. However, you cannot recover detail that AAC discarded during its original encoding. If the MOV source used a high-quality AAC bitrate (192k or above), the result in CAF will be a faithful uncompressed representation of that audio.
WAV has a 4GB file size ceiling due to its 32-bit chunk size header, which means a long uncompressed stereo recording at 44.1kHz can hit this limit after roughly 6–7 hours. CAF uses 64-bit chunk sizes and has no practical file size limit, making it the correct Apple-ecosystem format for extended recordings such as multi-hour field audio, conference captures, or long-form interviews extracted from MOV. CAF also natively supports non-interleaved audio and packet tables that improve seeking in large files.
Yes — FFmpeg reads the sample rate and channel layout from the MOV's audio stream and writes them into the CAF output by default. If the MOV contained 48kHz stereo audio (common for video recorded on Apple devices), the CAF will also be 48kHz stereo PCM. No resampling or channel remixing occurs unless you explicitly add flags like -ar or -ac to the command.
Yes. CAF is a first-class format in Apple's AVFoundation and AudioToolbox frameworks, and Xcode accepts CAF files as audio assets. PCM-encoded CAF files play back without any decoding overhead in apps targeting Apple platforms. This makes the MOV-to-CAF workflow particularly useful for game developers or app developers who want to pre-process audio from video sources into a format ready for direct inclusion in an Xcode project.
Replace -c:a pcm_s16le with -c:a flac in the command: ffmpeg -i input.mov -vn -c:a flac output.caf. CAF supports FLAC encoding, which gives you lossless audio at a significantly smaller file size than raw PCM — typically 40–60% smaller for typical speech or music. You can also use -c:a aac for a smaller lossy output, or -c:a pcm_s24le for 24-bit PCM if your source was recorded at higher bit depth.
Yes. On macOS or Linux, you can wrap the command in a shell loop: for f in *.mov; do ffmpeg -i "$f" -vn -c:a pcm_s16le "${f%.mov}.caf"; done. This iterates over every MOV file in the current directory and produces a matching CAF file with the same base filename. On Windows Command Prompt, use: for %f in (*.mov) do ffmpeg -i "%f" -vn -c:a pcm_s16le "%~nf.caf". The in-browser tool processes one file at a time, so the FFmpeg command is especially valuable for bulk workflows.
Technical Notes
The pcm_s16le codec writes 16-bit signed integer PCM samples in little-endian byte order — this is the same sample format used by standard CD audio and is universally compatible with Apple's CoreAudio stack. If your MOV source was recorded at 24-bit depth (common with professional cameras and audio interfaces), you may want to substitute pcm_s24le to avoid truncating the bit depth. The -b:a 128k flag in the command has no practical effect on PCM output since PCM is uncompressed and its bitrate is determined entirely by sample rate, bit depth, and channel count rather than a target bitrate parameter — it is included in the resolved command but is effectively ignored by FFmpeg for lossless codecs. CAF does not support subtitle streams, chapter markers, or multiple named audio tracks in the same way MOV does, so any chapter metadata or non-audio tracks in the source MOV will not carry over. The CAF format is Apple-specific and is not natively supported on Windows or Linux without additional libraries, so if cross-platform compatibility is a concern, consider WAV (for files under 4GB) or FLAC as alternatives.