Audio Extractor

Yes. Zolkit's Audio Extractor processes your video entirely inside your browser using WebAssembly. Your file is never uploaded to a server. The audio engine (~30 MB) is downloaded once and cached locally — after that, extraction works completely offline.

MP3 is the most compatible format — plays on every device and app. AAC is Apple's format and is slightly more efficient than MP3 at the same bitrate. WAV and FLAC are lossless — they preserve every detail of the original audio, but produce much larger files. FLAC is a compressed lossless format (roughly half the size of WAV). For casual listening, MP3 at 192 kbps is indistinguishable from the original. Choose WAV or FLAC only if you plan to do further audio editing.

This cannot happen with WAV or FLAC extraction. For MP3/AAC/OGG, the output quality is determined by the bitrate you choose. If the original video had low-quality audio (e.g., a compressed 96 kbps AAC track), outputting it at 320 kbps MP3 won't improve it — the quality ceiling is set by the source. In that case, choose Standard (192 kbps) to avoid inflating the file size for no benefit.

Upload the MOV file directly — Zolkit reads it natively without any conversion step. iPhone MOV files contain AAC audio at 44.1 kHz. Set format to MP3 and quality to High (320 kbps) for a clean conversion. A 1-minute iPhone video typically yields a 2–5 MB MP3 file.

Yes. FFmpeg automatically selects the default audio track (usually the first track). For most videos — movies, recordings, screen captures — there is only one audio track and the extraction is straightforward.

Zolkit does not enforce a file size cap. The practical limit is your device's available RAM. Most modern computers handle files up to 1–2 GB without issues. Audio extraction is much less memory-intensive than video compression because only the audio stream is decoded and re-encoded.