SWF to 3G2 Converter

Convert SWF to 3G2

3G2 is the multimedia container defined by 3GPP2 for CDMA2000 mobile networks — the counterpart to 3GP, which 3GPP defined for the GSM and UMTS side. Both are built on the ISO base media file format, the same foundation as MP4, and both were designed when a phone screen was a couple of hundred pixels wide and bandwidth was billed by the kilobyte. This converter reads the video and audio streams embedded in a .swf, re-encodes them, and writes a .3g2 file.

Adobe stopped supporting Flash Player on December 31, 2020 and began blocking Flash content on January 12, 2021. Nothing here emulates the Flash runtime — we decode streams stored in the container, not artwork that ActionScript would have drawn at playback time.

How to Convert SWF to 3G2

1. Upload Your SWF File: Drag the .swf onto the page or click "+ Add Files". Several files can be queued and converted with one set of settings.
2. Choose a Video Codec: H.264, H.263, MPEG-4 and Xvid are available. H.264 is the modern choice and imposes no size restrictions; H.263 is the legacy one and behaves very differently, as described below.
3. Choose an Audio Codec explicitly: AAC, AMR Narrow Band and AMR Wide Band are offered. Set this deliberately rather than accepting whatever is preselected — AAC for music and general audio, AMR only for speech.
4. Convert and Download: Click "Convert" and download the .3g2. Files upload over an encrypted connection, are processed on our servers, and are deleted automatically after a few hours — no sign-up, no watermark.

H.263 Will Resize Your Video Without Asking

This is the one behaviour on the page that can genuinely surprise you, and it only happens if you select H.263 in the Video Codec list.

H.263 is not a free-form codec: it accepts a short list of fixed picture sizes and nothing else. Rather than failing the job, our pipeline snaps the frame to the largest legal size that fits inside the source — and that snap overrides whatever you chose under Video resolution, and does not preserve the aspect ratio.

Every entry is 4:3. A widescreen source therefore gets squashed: a 16:9 frame snapped to 704 x 576 is horizontally compressed, and no resolution setting on the page will prevent it. Since most Flash video was authored at 4:3 anyway, this often passes unnoticed — but if your source is widescreen, pick H.264 instead, which honours the Video resolution control normally and produces a far better picture at the same size.

3G2 Compared With Its Neighbours

3G2 also carries a couple of deliberate restrictions relative to 3GP — it cannot store HE-AAC v2 or AMR-WB+ streams, for instance. Unless you are specifically targeting old CDMA hardware or matching an existing archive, SWF to MP4 produces a smaller, better-looking file that plays on far more devices.

Frequently Asked Questions

Why did my Flash file fail to convert?

Most likely because it contains no encoded video stream. The majority of surviving .swf files are vector timelines — games, banner ads, menus, cartoons — in which the artwork was stored as shapes and scripts and redrawn by the Flash Player each frame, never as pixels. There is nothing in such a file for a stream-reading converter to decode. Encrypted and protection-wrapped SWFs fail as well. Only a genuine Flash emulator such as the open-source Ruffle can display that kind of file, and you would be capturing its playback rather than converting it.

Should I pick AAC or AMR for the audio?

AAC for anything with music, sound effects or general audio — it handles a full frequency range and stereo. AMR Narrow Band is a speech codec: it is fixed at 8 kHz mono, which is telephone bandwidth, and it makes music sound thin and watery. AMR Wide Band is fixed at 16 kHz and is still speech-oriented. Since Flash soundtracks are usually music or effects, AAC is the right default; choose AMR only when you are matching an old handset's requirements and the content really is voice.

What resolution should I target?

Leave Video resolution on "Keep original" in most cases. Flash video was typically authored small — 320 x 240 and 480 x 360 were everywhere — and upscaling enlarges the existing compression artefacts rather than adding detail. If you do need to reduce it, note that the preset list sets the height and lets the width follow the source aspect, so a preset is not a fixed width-by-height pair. And if you selected H.263, none of this applies: the codec's fixed-size snap overrides your choice entirely.

Will a 3G2 file play on my phone?

Probably not on a modern one without help. Today's Android and iOS devices expect MP4; .3g2 was built for CDMA feature phones of the 2000s and support has quietly faded from mainstream players. VLC and ffmpeg-based tools open it on a desktop without trouble. If the goal is simply to watch old Flash content on a phone, MP4 is the format to convert to.

Can I trim the video to just the part I need?

Not from the .swf directly. A Flash file is not seekable — there is no index for a decoder to jump into — so requesting a start offset inside the SWF will not produce the section you asked for. Convert the whole movie, then cut the result in a format that seeks properly. This is also the only reliable way to learn the real duration, because a SWF header declares a frame count and a frame rate rather than a length.

What is the actual difference between 3G2 and 3GP?

They come from two different standards bodies serving two different network families: 3GPP2 defined 3G2 for CDMA2000 carriers, 3GPP defined 3GP for GSM and UMTS. Structurally they are near-identical ISO base media files, and the real divergence is in the audio codecs each permits — 3G2 adds CDMA-specific speech codecs such as EVRC and QCELP while excluding some 3GP options. In practice, choose whichever one your target device or archive expects; if neither applies, SWF to 3GP and this page produce equivalent results.

Is the audio kept in the conversion?

Yes, if the SWF actually stores an audio stream — it is decoded and re-encoded to your chosen Audio Codec. Where the Flash sound was triggered by ActionScript at runtime rather than stored, there is nothing to carry over and the output has video only. Bear in mind that AMR will resample whatever it receives to its own fixed rate, so a 44.1 kHz music track selected as AMR-NB comes out at 8 kHz mono.

Why does the output look worse than the Flash original?

Two effects stack. Every conversion here re-encodes rather than copying streams across, so one generation of quality is spent no matter what settings you use. On top of that, 3G2 was designed around codecs and bitrates suited to 2000s mobile networks, and H.263 in particular is far weaker than anything modern. Selecting H.264 and a high Quality Preset recovers most of the difference; converting to MP4 instead recovers the rest.

What happens to my SWF file after the conversion?

Your file is uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — never shared, never made public, and never used for anything other than producing your download.