MyMediaTools

Convert 3GPP to 3G2 — Free Online Tool

Convert 3GPP (.3gp) files to 3G2 (.3g2) format, switching from GSM/WCDMA mobile standards to the CDMA-based 3GPP2 container used by CDMA carriers like Verizon and Sprint-era devices. Both formats share H.264 video and AAC audio codec support, making this a near-lossless container migration with a default CRF 23 re-encode.

FFmpeg Command

Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg

Free — no uploads, no signups. Your files never leave your browser.

Estimated output:

Conversion Complete!

Download

How It Works

Despite their similar origins, 3GPP and 3G2 are distinct container standards built for different mobile network families — GSM/WCDMA versus CDMA2000. During this conversion, FFmpeg decodes the H.264 video stream from the .3gp container and re-encodes it into the .3g2 container using libx264 at CRF 23, which is a visually near-transparent quality level. The AAC audio track is similarly re-encoded at 128k bitrate — notably higher than the 3GPP default of 64k, giving the output slightly better audio fidelity. The -movflags +faststart flag reorganizes the MP4-family metadata (the 'moov' atom) to the front of the file, enabling progressive playback before the full download completes. Because both containers share the same underlying codec support, no dramatic quality degradation should occur, though any re-encoding introduces a small generation loss.

What Each Flag Does

Flag What it does
ffmpeg Invokes the FFmpeg binary — the open-source multimedia processing engine that handles decoding the 3GPP input, re-encoding the streams, and writing the 3G2 output container. In the browser tool, this runs via FFmpeg.wasm compiled to WebAssembly.
-i input.3gp Specifies the input file in 3GPP format (.3gp), the GSM/WCDMA mobile multimedia container. FFmpeg reads and demuxes the H.264 video and AAC or MP3 audio streams from this container before processing.
-c:v libx264 Sets the video encoder to libx264, encoding the output video stream as H.264 — the same codec used in the source 3GPP file. This re-encodes rather than stream-copies to ensure full compliance with the 3G2 container's track structure requirements.
-c:a aac Sets the audio encoder to AAC, the default and most compatible audio codec for the 3G2 container. The audio is re-encoded from the source 3GPP audio stream (typically AAC or MP3) into AAC for the CDMA-standard 3G2 output.
-crf 23 Sets the Constant Rate Factor for the libx264 video encode to 23, which is the standard default and produces visually near-transparent quality for typical mobile video content. Lower values (toward 0) mean higher quality and larger file size; higher values (up to 51 in 3G2) produce smaller, lower-quality video.
-b:a 128k Sets the AAC audio bitrate to 128 kilobits per second, which is the default for the 3G2 output format and notably higher than the 3GPP tool's default of 64k. This gives the converted 3G2 file better audio clarity than the source 3GPP file may have had, at the cost of a slightly larger audio stream.
-movflags +faststart Triggers a post-encoding step that relocates the MP4-family 'moov' metadata atom from the end of the file to the beginning. This is important for the 3G2 output because it allows CDMA devices and streaming-capable players to begin playback before the entire file has been transferred.
output.3g2 Specifies the output filename with the .3g2 extension, which signals FFmpeg to write the result into the 3GPP2 container format. The .3g2 extension is the standard file type for CDMA2000 mobile multimedia content.

Common Use Cases

  • Archiving old video MMS messages or media clips originally recorded on a GSM/WCDMA phone for playback on a CDMA device or legacy Verizon handset that only accepts .3g2 files
  • Preparing short video clips from 3GPP-based feature phones for upload to platforms or apps that specifically require the 3GPP2/3G2 container format
  • Converting a .3gp video captured on an older Nokia or Sony Ericsson handset into .3g2 for compatibility with CDMA carrier media portals or ringtone/video stores from the mid-2000s era
  • Digitizing and re-containerizing legacy mobile video content from GSM-era devices into the 3G2 format for long-term archival in a CDMA-standardized library
  • Batch-migrating a collection of .3gp clips produced by a video converter or media tool into .3g2 to satisfy a specific downstream software pipeline or hardware decoder requirement
  • Re-packaging 3GPP footage for editing in software that imports 3G2 but does not recognize the raw .3gp extension or its specific box structure

Frequently Asked Questions

Both are MP4-derived multimedia containers, but .3gp was standardized by 3GPP for GSM and WCDMA mobile networks, while .3g2 was developed by 3GPP2 for CDMA2000 networks used by carriers like Verizon and Sprint. They share virtually the same codec support (H.264, AAC, MP3, MJPEG), but differ in their box/atom structure definitions and metadata specifications. In practice, many modern players handle both, but dedicated CDMA-era devices and software often require .3g2 explicitly.
Yes, a small amount of quality loss occurs because FFmpeg re-encodes the video with libx264 at CRF 23 rather than performing a lossless stream copy. However, CRF 23 is considered visually transparent for most content, meaning differences are unlikely to be perceptible to the naked eye. The audio actually improves slightly in bitrate — going from the 3GPP tool's default of 64k to 128k AAC in the 3G2 output — though this re-encoding still introduces a generation of lossy compression.
While both .3gp and .3g2 support H.264 video, the containers use slightly different internal atom/box structures and track type definitions specified by their respective standards bodies. FFmpeg defaults to re-encoding in this conversion to ensure full compliance with the 3G2 container specification rather than risk embedding a stream with 3GPP-specific track metadata. If you are confident your source video uses standard H.264 baseline profile, you could attempt stream copying by replacing '-c:v libx264 -crf 23' with '-c:v copy', though compatibility with strict 3G2 decoders is not guaranteed.
Change the CRF value in the command — lower numbers produce higher quality at larger file sizes, and higher numbers reduce quality while shrinking the file. For this 3GP-to-3G2 conversion, the supported CRF range in the 3G2 output is 0 (near-lossless) through 51 (very low quality), with the default at 23. For example, using '-crf 18' will produce noticeably sharper video but a significantly larger .3g2 file, which may matter on mobile storage-constrained devices. To also adjust audio quality, change '-b:a 128k' to values like '64k', '96k', or '192k'.
No — the 3G2 format does not support subtitles, chapter markers, or multiple audio tracks, and neither does the 3GPP source format. This conversion is strictly a single video stream plus single audio stream migration. Any such metadata present in a wrapped source would be dropped during the conversion. If you need these features, you should convert to a more capable container like MP4 or MKV instead.
Yes, you can adapt the displayed command into a simple shell loop. On Linux or macOS, run: 'for f in *.3gp; do ffmpeg -i "$f" -c:v libx264 -c:a aac -crf 23 -b:a 128k -movflags +faststart "${f%.3gp}.3g2"; done'. On Windows Command Prompt, use: 'for %f in (*.3gp) do ffmpeg -i "%f" -c:v libx264 -c:a aac -crf 23 -b:a 128k -movflags +faststart "%~nf.3g2"'. The in-browser tool on this page processes one file at a time, so the command-line approach is recommended for batch jobs.

Technical Notes

Both 3GP and 3G2 are derivatives of the MPEG-4 Part 12 base container, which is itself derived from Apple's QuickTime MOV format, explaining their structural similarity and shared codec ecosystem. However, 3G2 was specifically extended by 3GPP2 to include CDMA2000-specific timing and synchronization metadata, as well as provisions for EVRC and QCELP audio codecs not present in the standard 3GPP specification. This FFmpeg conversion uses libx264 with the default H.264 encoding settings targeting the 3G2 container, but note that original 3GPP files may have used very low-bitrate, low-resolution H.264 Baseline Profile encoding optimized for WCDMA bandwidth constraints — re-encoding at CRF 23 will not recover detail lost in that original encode but will faithfully preserve what remains. The -movflags +faststart flag moves the 'moov' atom to the beginning of the output file, which is important for streaming but adds a small post-processing step. Neither format supports transparency, subtitles, chapters, or multiple audio tracks, so metadata in those categories from any source is silently discarded. File sizes between .3gp and .3g2 outputs at equivalent settings are typically very close, as the overhead difference in container metadata is negligible compared to media stream data.

Related Tools

Convert 3GPP to GIF Convert 3GPP to VOC Convert 3GPP to MP3 Convert RM to 3G2 Convert WMV to 3G2 Convert AVI to 3G2 Compress 3GPP Extract Audio 3GPP to MP3