MTS to 3GP Converter

Convert MTS to 3GP: What This Tutorial Covers

This walks through turning an AVCHD camcorder .MTS clip into a .3gp file — and, just as importantly, when you should not. 3GP is a feature-phone container from the early 2000s, so this conversion deliberately shrinks HD footage down to a small-screen format; if you just want your camcorder video to play on a modern phone or computer, use MTS to MP4 instead, which keeps the original quality.

Read This First: MTS to 3GP Is a Big Downgrade

MTS is the on-camera name for AVCHD, the HD camcorder format Sony and Panasonic introduced in 2006. It carries H.264 video at up to 1920x1080 (24 Mbit/s, or 28 Mbit/s for AVCHD Progressive 1080p60) with Dolby AC-3 audio. 3GP is the opposite end of the scale: a 3GPP container released in 2003 for 3G feature phones, built around tiny resolutions like QCIF (176x144) and the speech-optimized AMR audio codec.

Converting MTS to 3GP throws away most of that HD detail. The picture is downscaled toward phone-era dimensions, and with the default AMR Narrow Band audio the soundtrack is resampled to 8 kHz mono — fine for spoken voice, but it makes music and ambient sound muffled and telephone-grade. Only pick 3GP if a specific old device or piece of software actually requires it. Realistic reasons:

• Playback on a genuinely old feature phone or basic handset that only accepts .3gp.
• Feeding legacy MMS-era tooling, kiosk hardware, or a test rig that expects the 3GPP format.
• Reproducing the exact look of an old mobile clip.

For everything else — sharing, editing, uploading, or watching on any current phone, TV, or browser — MTS to MP4 is the right choice and loses none of the quality.

How to Convert MTS to 3GP

1. Upload Your MTS File: Drag and drop, or click "+ Add Files" to select clips from your computer or a mounted SD card. AVCHD camcorders store streams under PRIVATE/AVCHD/BDMV/STREAM/ with 8.3-style names like 00001.MTS. Batch upload is supported.
2. Pick a Quality Preset: Leave File Compression on the default "Very High (Recommended)" preset, or step down to Medium/Low to make the file even smaller — sensible for a format aimed at tiny screens. Specific file size lets you target a hard megabyte budget.
3. Set Resolution and Codecs (Optional): Under Video resolution, choose a Preset Resolution such as 240p or 360p to match an old handset, or keep original. Under Advanced Options the Video Codec defaults to H.264 (switch to H.263 for maximum compatibility with the oldest 3GP players); the Audio Codec defaults to AMR Narrow Band — change it to AAC if you want listenable music instead of speech-grade sound, when your target device supports it.
4. Convert and Download: Click Convert. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically a few hours after conversion — no sign-up, no watermark, never shared. Download each clip or grab everything as a ZIP.

Walk-through: Choosing Resolution and Audio for an Old Device

The two settings that decide whether your 3GP actually plays — and sounds right — are resolution and audio codec. The classic 3GP target is QCIF (176x144) for the oldest phones; later 3G handsets handle QVGA (320x240) and some go higher. Modern players (VLC, MX Player) will open almost any 3GP regardless. Match the file to the oldest device you need to support:

• Oldest feature phones / maximum compatibility: set Video Codec to H.263, Video resolution to a low preset (240p or below), and leave Audio Codec on AMR Narrow Band. This is the most universally playable 3GP, at the cost of the most quality loss.
• Later 3G smartphones: Video Codec H.264, resolution 360p, Audio Codec AAC gives a sharper picture and real (non-speech) audio while staying inside the 3GP container.
• Voice-only clips (interviews, memos): AMR Narrow Band is genuinely the right pick — it is purpose-built for speech at 8 kHz and produces very small files.

If you are unsure what your device accepts, the safe default of H.264 video plus AMR audio matches what most 3GP playback expects, but test one short clip before converting a whole batch.

Common Errors and How to Fix Them

• "Output plays but the picture is tiny or blocky" — that is 3GP working as designed; it is a small-screen format. If you wanted full quality, convert to MTS to MP4 instead.
• "Music sounds muffled or like a phone call" — the default AMR Narrow Band codec is speech-only at 8 kHz. Switch Audio Codec to AAC for music and ambience.
• "The old phone refuses to play the file" — the device likely needs H.263 video at QCIF/QVGA resolution. Set Video Codec to H.263 and pick a 144p or 240p preset.
• "Audio is gone in my editor" — many desktop editors do not decode AMR. Re-convert with AAC audio, or convert to MP4 for a track every editor reads.
• "File is still larger than I expected" — drop the Quality Preset to Medium or Low, or lower the resolution preset; 3GP size scales with both.

When This Doesn't Work

If your goal is anything other than feeding a legacy 3GP-only device, this conversion is the wrong tool — you are paying a steep quality cost for no benefit. Use MTS to MP4 for universal modern playback that preserves the HD picture. Converting the other direction (an old 3GP up to an AVCHD camcorder stream) is handled by 3GP to MTS, though upscaling a phone clip cannot add back detail it never had. And if an MTS file is from a damaged SD card or a partial recording, it may fail to decode cleanly in any converter — copy the full BDMV folder off the card first rather than a single loose .mts.

Frequently Asked Questions

Will MTS to 3GP lose quality?

Yes, substantially. 3GP is built for small phone screens, so the HD H.264 video from your AVCHD camcorder is downscaled and the audio, by default, is reduced to speech-grade AMR. This is unavoidable with the format — it is the point of 3GP, not a flaw in the converter. If you want to keep the original 1080p detail, convert to MP4 instead.

Does 3GP include sound, and why does it sound like a phone call?

Yes, 3GP carries audio, but its default codec here is AMR Narrow Band, a speech codec that samples at 8 kHz mono — the same family used for mobile voice calls. That is why music and background sound come out muffled. Select AAC under Audio Codec for full-range audio, provided your target device can play AAC inside 3GP.

What plays a 3GP file?

Older feature phones and 3G smartphones play 3GP natively, and on the desktop VLC and MX Player open it without extra codecs. It is not natively supported by modern desktop browsers the way MP4 is, so if you need browser or smart-TV playback, 3GP is the wrong format — use MP4.

Should I pick H.263 or H.264 for the video codec?

Use H.263 for the broadest compatibility with the oldest 3GP-era phones; it is the codec those handsets were designed around. Use H.264 (the default) for a noticeably sharper picture on any later device that supports it inside 3GP. When in doubt and targeting very old hardware, H.263 is the safer bet.

Is there a file size limit, and how long are my files kept?

There is no fixed per-file cap — the practical limit is upload size and connection speed, since files are processed on our servers. In our testing, a 1-minute 1080p MTS clip converted to a 240p H.263 / AMR 3GP came out around 2-3 MB, versus roughly 150 MB for the source, which shows how aggressively the format compresses. Uploaded and converted files are deleted automatically a few hours after conversion and are never shared or made public.

Can I convert a whole camcorder reel of MTS clips at once?

Yes. Add multiple .MTS files and they convert with the same settings, then download individually or as a ZIP. Because 3GP files are so small, even a large batch of clips produces a modest total — but remember every clip takes the same heavy quality cut, so confirm 3GP is really what the target device needs before batch-converting.