Key difference: Both, 3GP and 3G2 are file formats mainly used for playing videos with audios. However, what most people do not realize that 3GP and 3G2 are not encoding formats, but are container files, i.e. basically wrappers for formatted video files. 3GP is a multimedia container format mainly for 3G UMTS multimedia services. It was developed by the Third Generation Partnership Project (3GPP). Similar to 3GP, 3G2 is a multimedia container format mainly for 3G multimedia services. It was developed by the Third Generation Partnership Project 2 (3GPP2). As 3GPP defines the standard for GSM based phones, 3GPP2 defines the standard for CDMA based phones.

Both, 3GP and 3G2 are file formats mainly used for playing videos with audios. However, what most people do not realize that 3GP and 3G2 are not encoding formats, but are container files, i.e. basically wrappers for formatted video files.

A container file specifies how the data streams inside it are organized. The actual organization and representation of the data streams are done by the various types of codecs (encoder/decoder). It is the codecs that affects video quality and compression. It describes how video or audio data is to be compressed and decompressed. Each container file will differ only on the basis of which codec is used.

3GP is a multimedia container format mainly for 3G UMTS multimedia services. It was developed by the Third Generation Partnership Project (3GPP). It is commonly used on 3G mobile phones; however, some 2G and 4G phones use it as well.

3GP is part of the 3GPP Standards and is a container file for various audio and video file formats. It was designed and is still mainly used for IP Multimedia Subsystem (IMS), Multimedia Messaging Service (MMS), Multimedia Broadcast/Multicast Service (MBMS) and Transparent end-to-end Packet-switched Streaming Service (PSS).

Similar to the MP4 container file format, 3GP was also based on the ISO base media file format defined in MPEG-4 Part 12. However, older versions of the 3GP file format did not use some of its features. Most 3GP files use the filename extension .3gp; however some cell phones use the extension .mp4 for the same 3GP files.

The 3GP file format was designed mainly for GSM-based phones. The format was designed to decrease storage and bandwidth requirements in order for the video/audio files to be accommodated for mobile phones

Usually the 3GP container file contains H.263 (MPEG-4 Part 2) encoded video; however H.264 (MPEG-4 Part 10/ AVC) encoded video are getting more common as well. In audio, 3GP usually contains various AMR, AAC and ACC+ formats.

Similar to 3GP, 3G2 is a multimedia container format mainly for 3G multimedia services. It was developed by the Third Generation Partnership Project 2 (3GPP2). The 3GPP2 was the second collaboration between global telecommunications associations. As 3GPP defines the standard for GSM based phones, 3GPP2 defines the standard for CDMA based phones. The filename extension for 3G2 is .3g2.

3G2 is very similar to the 3GP file format, such as both are container formats based on the MPEG-4 Part 12 media file format. Both were designed to decrease storage and bandwidth requirements in order to accommodate mobile phones. However, 3G2 does have some extensions and limitations as compared to 3GP.

The 3G2 container file format can store all the same video streams and most of the audio streams as 3GP. 3G2 can also store various EVRC audio streams, 13K (QCELP), SMV and VMR audio streams. However, 3G2 does not store ACC+ and AMR-WB+ audio streams. 3G2 also contains some enhancements to 3GPP Timed Text.

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