Convert 3G2 to 3GP — Free Online Converter

3G2 and 3GP are sibling mobile video containers born from competing cellular standards of the early 2000s. 3G2 (3GPP2) was created for CDMA2000 networks operated by carriers like Verizon and Sprint in the United States, while 3GP (3GPP) was designed for GSM/UMTS networks used by AT&T, T-Mobile, and the vast majority of international carriers. Despite sharing nearly identical codec support — H.263 or MPEG-4 Part 2 video with AMR or AAC audio — the two formats differ in container metadata headers and ftyp brand atoms, which can cause playback failures when files cross between network ecosystems.

Converting 3G2 to 3GP bridges the divide between these two mobile worlds. Since both formats use the same underlying codecs, the conversion is a container remux that copies video and audio bitstreams into the 3GPP container without re-encoding. The operation is virtually instantaneous and preserves original quality bit-for-bit. This is the simplest way to make CDMA phone recordings universally playable on legacy GSM devices and older multimedia messaging systems.

The primary reason to convert 3G2 to 3GP is cross-carrier compatibility on legacy devices. Videos recorded on old CDMA phones from Verizon or Sprint may not open on GSM-era feature phones from AT&T, T-Mobile, or international carriers that only recognize the .3gp extension and 3GPP container headers. The 3GP format enjoys far broader global support since GSM was the dominant cellular technology worldwide, serving over 80% of mobile subscribers during the feature phone era.

Additionally, many older media players, editing tools, and web platforms recognize 3GP but not 3G2. MMS messaging systems on GSM networks typically accept only the 3GPP variant for video attachments. If you are archiving a collection of old mobile phone recordings, standardizing on 3GP reduces format fragmentation and simplifies long-term library management. The conversion cost is essentially zero — no quality loss, no significant processing time, and no increase in file size.

Both 3G2 and 3GP are based on the ISO base media file format (ISO 14496-12). 3G2 uses ftyp brand '3g2a' or '3g2b' from the CDMA2000 multimedia framework, while 3GP uses '3gp4', '3gp5', or '3gp6' from the 3GPP specification. FFmpeg handles the conversion by remuxing — copying the existing H.263 or MPEG-4 Part 2 video and AMR-NB or AAC audio bitstreams into the new container without transcoding. The ftyp atom and container metadata are rewritten to match the 3GPP standard, making the operation virtually instantaneous regardless of file size.