Free online MTS to 3GP converter

Source format overview

MTS is a video file format commonly used by AVCHD camcorders from Sony, Panasonic, Canon, and other manufacturers. It usually contains H.264/AVC video with AC-3 or LPCM audio inside an MPEG transport stream container. MTS files are typically used for high-definition camera recordings, home videos, and footage imported from memory cards or camcorders.

Target format overview

3GP is a multimedia container originally designed for mobile phones and low-bandwidth playback. It is based on the MPEG-4 family and is often used for small file sizes, broad device compatibility on older phones, and quick sharing over limited connections. Compared with MTS, 3GP usually offers much lower resolution and bitrate, which makes it suitable for lightweight playback rather than archival quality.

How to perform the conversion

The most reliable way to convert .mts to .3gp is with FFmpeg, because it gives precise control over video and audio settings and works on Windows, macOS, and Linux.

1. Install FFmpeg if it is not already available on your system.
2. Open a terminal or command prompt in the folder containing the MTS file.
3. Run a conversion command such as ffmpeg -i input.mts -c:v libx264 -preset medium -crf 28 -vf scale=320:-2 -c:a aac -b:a 64k output.3gp.
4. Check the resulting file in a media player or on the target device.

This command re-encodes the video to H.264, scales it to a small mobile-friendly size, and converts audio to AAC, which is commonly supported in 3GP containers. If you need even smaller files, you can lower the resolution further or increase the CRF value slightly.

If you prefer a graphical workflow, use VLC, HandBrake, or FFmpeg-based desktop tools that allow export to mobile-oriented formats. In many cases, the conversion can also be done on the 101convert.com website for free, without installing any software.

Notes on quality and compatibility

3GP is a highly compressed target format, so converting from MTS usually means a noticeable loss of detail, especially if the source is full HD or 4K. This is normal and expected because 3GP is intended for small screens and low bitrates.

Compatibility depends on the device and player. Some older devices support only AMR audio or very specific 3GP profiles, while newer players may accept AAC in 3GP. If playback fails, try lowering the resolution, using a simpler codec profile, or exporting to 3G2 instead if the device expects that variant.

Because MTS often contains interlaced or high-bitrate footage, you may also need deinterlacing or bitrate reduction for smoother playback. For best results, keep the output resolution modest and test the file on the intended device before converting a large batch.