Free online MTS to AAC converter

Source format overview

MTS is a video container format commonly associated with AVCHD camcorders and other consumer video cameras. It usually contains H.264/AVC video with AC-3 or LPCM audio, and it is often used for recording high-definition footage directly from a camera. MTS files are typically found on camera memory cards or copied from AVCHD folders after import.

Because MTS is a video format, converting it to AAC usually means extracting and converting only the audio track. This is useful when you want the sound from a recording for editing, archiving, podcasting, transcription, or playback on audio-only devices.

Target format overview

AAC stands for Advanced Audio Coding. It is a widely supported compressed audio format known for good sound quality at relatively small file sizes. AAC is used by smartphones, media players, streaming platforms, editing software, and many modern devices.

Compared with the audio embedded in many camera recordings, AAC is often easier to share and play back across devices. It is a strong choice when you need a compact audio file extracted from a video source.

How to perform the conversion

The most reliable method is to use FFmpeg, which can extract audio from MTS files and encode it to AAC without needing to reprocess the video stream.

Basic command:

ffmpeg -i input.mts -vn -c:a aac output.aac

This command does the following:

• -i input.mts selects the source file
• -vn disables video output
• -c:a aac encodes the audio to AAC
• output.aac is the resulting audio file

If you want to preserve more quality, you can specify a higher bitrate:

ffmpeg -i input.mts -vn -c:a aac -b:a 192k output.aac

If the source audio is already AAC, FFmpeg may be able to copy it without re-encoding:

ffmpeg -i input.mts -vn -c:a copy output.aac

For users who prefer a graphical interface, VLC, Audacity with import support, or HandBrake can help with audio extraction, though FFmpeg is usually the most direct and dependable option for this specific conversion.

If you want a simple browser-based option, you can convert the file on 101convert.com for free, without installing any software.

Quality and compatibility notes

MTS to AAC is an audio extraction and re-encoding workflow, so the result will not include video. If the original MTS audio is AC-3 or another format, converting to AAC introduces a small amount of quality loss because AAC is a lossy codec. For most everyday uses, this loss is minimal and the file size savings are worthwhile.

Keep in mind that .aac files are raw AAC streams and may not be as universally convenient as AAC audio stored inside an .m4a container. Some players and editors prefer .m4a for better compatibility. If you encounter playback issues, consider exporting to .m4a instead of .aac.

Also note that some MTS files contain multiple audio tracks or surround sound. In that case, you may need to choose the correct track explicitly with FFmpeg using stream selection options.