CONVERTIR
MP4 → M4A

Yes. The free tier accepts files up to 100 MB without registration, email capture or watermarks. Paid plans raise the size cap, enable batch conversions and provide a REST API for automation, but nothing on the free tier is quality-limited — the output is exactly the same as on any paid plan.

Only if the audio codec inside MP4 is not directly writable into the M4A container. When codecs match we stream-copy, producing a bit-exact M4A. When they differ, we re-encode at a high-quality default, so the perceptual loss is tiny for anything other than lossless-to-lossless mismatches.

Uploads run over HTTPS, files are processed in isolated containers, and both the source MP4 and the M4A output are auto-deleted within two hours. No account is required, file contents are never logged, and KaijuConverter does not use uploads for AI training. The paid plan adds a signable data-processing agreement for regulated workflows.

No. The full MP4 lands in our processing container, we demux the audio locally and then the container is destroyed. The video bytes never leave KaijuConverter infrastructure and auto-delete within two hours along with the original file.

Most files finish in well under a minute. Small images and documents are typically ready in a few seconds; large video or audio files scale roughly with duration. Upload speed from your network is usually the dominant factor, not server time.

Yes. The Advanced options let you set start and end times in HH:MM:SS, so you can extract a single chapter, a specific quote or a clean sample instead of the full duration of the MP4.