3GPP to 3G2 Converter

3GPP vs 3G2 — What Actually Changes

Both files are mobile-video containers built on the ISO base media file format, the same foundation MP4 sits on. .3gpp is the 3GPP format from the GSM and UMTS world, and .3gp is simply the other spelling of it — identical bytes, identical structure. .3g2 is the 3GPP2 format, written for CDMA2000 handsets and defined in that body's File Formats for Multimedia Services specification, C.S0050.

The short answer to "what changes": the branding, and the list of audio codecs the container is allowed to hold. The video side is common ground — H.263, MPEG-4 Part 2 and H.264 are legal in both. So this conversion is a re-encode into a differently branded box, and the only reason to do it is that something downstream insists on the .3g2 extension or on a 3GPP2 brand identifier. If nothing does, 3GPP to MP4 is a better use of the same encode.

Side-by-side Comparison

When to Stay on 3GPP

• A GSM-era handset, MMS gateway or Symbian-era app is the destination — it expects the 3gp brand.
• The clip already plays where you need it to. Re-encoding costs a generation of quality and buys nothing.
• The audio track is HE-AAC v2 or AMR-WB+, neither of which 3G2 is allowed to store.
• You want the widest desktop support for a legacy mobile clip; .3gp is the better-recognised of the two extensions.

When to Convert to 3G2

• A CDMA2000 handset or a carrier gateway from that era rejects anything but .3g2.
• An archive, catalogue or ingest tool filters strictly on the 3GPP2 brand identifier rather than sniffing the file.
• A legacy application hard-codes the extension and will not open a renamed file, because renaming does not change the ftyp brand written inside.

How to Convert 3GPP to 3G2

1. Upload Your 3GPP File: Drag the .3gpp file onto the page or click "+ Add Files" to browse. Multiple clips can queue and they convert with a single set of settings.
2. Choose Video Codec: The dropdown offers H.263, H.264, MPEG-4 and Xvid, and opens on H.264 — the most efficient of the four and legal in both containers. Pick H.263 only if the receiving device is old enough to need it, and read the frame-size table below first.
3. Choose Audio Codec Explicitly: AAC, AMR Narrow Band and AMR Wide Band are the three the 3G2 container accepts here, and none of them arrives pre-selected — pick one rather than leaving the group untouched. AMR Narrow Band is the compatibility choice for old CDMA handsets; AAC is the quality choice for anything modern.
4. Set Resolution or Trim, Then Convert: Video resolution opens on Keep original; Trim opens on "Unchanged" and accepts a Time Range. Click Convert to download the .3g2. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark.

If You Pick H.263, the Frame Size Is Chosen for You

H.263 is not a free-form codec. It only encodes a short list of fixed picture sizes, and our pipeline conforms the frame to the largest one that fits inside your source rather than letting the encode fail. This overrides whatever you selected under Video resolution, and it does not preserve the aspect ratio.

The good news for this particular conversion is that genuine .3gpp phone footage is usually QCIF or CIF already, so both of those pass through untouched. The snap only bites when the source is larger than CIF — for example a .3gpp file produced by a desktop tool rather than a handset. Choosing H.264 avoids the whole issue, which is why it is the default.

Frequently Asked Questions

Is .3gpp a different format from .3gp?

No — they are two spellings of one container. Both are the 3GPP file format built on MPEG-4 Part 12, and a file written with either extension has identical bytes and an identical ftyp brand. Any player or tool that opens one opens the other. This page reads .3gpp uploads; if your file uses the shorter spelling, 3GP to 3G2 is the same conversion under the other name.

Can I just rename my .3gpp file to .3g2 instead of converting?

Sometimes it works, and it is not the same thing. Renaming changes the label on the outside while the ftyp box inside still declares a 3GPP brand. Players that sniff the container will play it regardless; tools that validate the brand identifier — which is precisely the kind of tool that made you want a .3g2 in the first place — will reject it. Converting rewrites the brand along with re-encoding the streams, so the file is genuinely a 3GPP2 file rather than a mislabelled 3GPP one.

Will I lose quality converting 3GPP to 3G2?

Yes, one generation of it, because this is a re-encode rather than a rewrap. The video is decoded and compressed again, and the audio is re-encoded into a codec the 3G2 container permits. The loss is small when the source is already low-bitrate phone footage and you leave Quality Preset high and resolution on "Keep original", but it is real. Convert once from your original file rather than chaining conversions.

What is the difference between AMR Narrow Band and AMR Wide Band?

Bandwidth, and both are fixed. AMR-NB runs at a fixed 8 kHz sample rate in mono and captures roughly the 200 Hz to 3.4 kHz telephone band — it is what nearly every 3G-era handset recorded. AMR-WB doubles that to a fixed 16 kHz sample rate, still mono, and reaches around 7 kHz, which makes speech noticeably clearer. Neither rate is adjustable, because the codecs themselves do not define other modes. If the source audio is already AMR-NB, choosing AMR-WB cannot recover the missing high frequencies — it only stores the same narrow band in a wider container.

Should I pick AAC instead of AMR for the audio?

Pick AAC if a modern device will play the file, and AMR if a legacy handset will. AAC is the better codec by a wide margin and 3G2 permits it, so if you are converting for a desktop tool or an archive there is no reason to accept a vocoder. AMR exists in this list because old CDMA handsets often decode nothing else, and because AMR-NB is what most source clips already contain — in which case re-encoding to AAC preserves the same narrow band at a larger file size.

What CDMA speech codecs does 3G2 add, and can this tool write them?

The 3G2 specification permits EVRC, EVRC-B, EVRC-WB, 13K (QCELP), SMV and VMR-WB — vocoders designed for CDMA2000 voice channels. This converter does not write them; the Audio Codec list on this page offers AAC, AMR Narrow Band and AMR Wide Band, all of which the 3G2 container also accepts and all of which have far broader decoder support. The CDMA vocoders were only ever produced by handsets and network equipment, and nothing outside that ecosystem decodes them reliably.

Will a .3g2 file play on a modern phone?

Often not, at least not by double-tapping it. The container is an MP4 relative and the video inside is usually decodable, but current iOS and Android media apps frequently do not associate the .3g2 extension with anything and refuse to open it. On a desktop, VLC plays .3g2 on Windows, macOS and Linux without extra codecs. If your goal is a file that opens everywhere rather than one with a specific extension, 3GPP to MP4 is the conversion you want.

How big will the 3G2 file be?

Close to the original, usually a little larger. In our testing a 10-second 352x288 clip of 402 KB came back as a 472 KB .3g2 encoded with the default H.264 video and an AMR Narrow Band soundtrack — the H.264 encode spends a few more bits than the source H.263 stream did at the default quality target. If you need it smaller, switch File Compression to Specific file size and name a figure, or step the Quality Preset down. Upscaling with the resolution presets is the one thing guaranteed to inflate the file without improving anything.

How are my files handled?

The .3gpp you upload travels over an encrypted connection, is converted on our servers, and both it and the resulting .3g2 are deleted automatically a few hours later. Files are never shared or made public, and no account is needed. Mobile clips are small, so conversion is normally quicker than the upload itself.