MP4 to 3G2 Converter

How to Convert MP4 to 3G2 Online

1. Upload Your MP4 File: Drag and drop or click "Add Files" to select MP4 or M4V video files. Modern smartphone recordings, downloaded clips, screen captures, and rendered exports all work. Batch is supported — queue several files for delivery to the same legacy CDMA target.
2. Pick a Video Codec: Default is H.264 for the broadest 3G2 player support. Choose H.263 for maximum compatibility with very old CDMA feature phones or MPEG-4 Part 2 if a downstream tool requires it. Set a Quality Preset (Highest -> Lowest), target a percentage of the original size, an exact size in MB/KB, Constant Bitrate, Variable Bitrate, Constant Quality (CRF 18 = visually lossless, 23 = default, 28 = smaller), or Constraint Quality (CRF + max bitrate cap).
3. Set Resolution and Audio (Optional): 3G2 was designed for small screens — pick a Preset Resolution (240p, 360p, 480p) or scale by Resolution Percentage to drop to QVGA (320x240) or QCIF (176x144). Default audio is AMR-NB; switch to AAC-LC for music clips that need better fidelity. Trim with start time + duration in HH:MM:SS.sss to extract just the segment you want to send.
4. Convert and Download: Click Convert. Files process in your browser session — no sign-up, no watermark, no third-party upload.

Why Convert MP4 to 3G2?

3G2 (3GPP2 Multimedia File) was published in January 2004 by the 3rd Generation Partnership Project 2 for CDMA2000 mobile networks — the cellular standard used in the US by Verizon Wireless, Sprint, US Cellular, and internationally by KDDI au in Japan. The container is byte-for-byte similar to the GSM-side 3GP spec (both are built on ISO Base Media / MPEG-4 Part 12), but 3G2 swaps the AMR audio family for CDMA-native voice codecs: EVRC, EVRC-B, EVRC-WB, 13K (QCELP), SMV, and VMR-WB. MP4, by contrast, is the universal modern video container with H.264 / H.265 / AAC. Common reasons people convert MP4 -> 3G2:

• Sending video via MMS to legacy CDMA feature phones — Verizon and Sprint MMS gateways from the pre-VoLTE era expect 3G2 with H.263 or low-profile H.264 video and AMR-NB or QCELP audio. An MP4 with HE-AAC will be silently rejected; a properly encoded 3G2 goes through.
• Test fixtures for legacy CDMA infrastructure — Carrier QA labs, MMS test rigs, and feature-phone emulator suites built around CDMA2000 still validate against 3G2 inputs. Converting from MP4 is the cleanest way to produce known-good test files.
• Restoring backups for old Verizon / Sprint / US Cellular phones — Photos and clips re-flashed onto a 2008 Verizon Razr or LG enV need to be in 3G2 with H.263 + AMR-NB to play through the native gallery without erroring.
• Embedded systems and kiosks specced for 3GPP2 — Some industrial signage, in-vehicle infotainment systems, and POS displays from the late 2000s only ingest 3G2. Converting incoming MP4 uploads is the cleanest fix.
• Bandwidth-constrained delivery to older mobile networks — 3G2 targets 64-384 kbps cellular bandwidth at 176x144 (QCIF) or 320x240 (QVGA), so the encoded file is far smaller than a typical 1080p MP4.
• Forensic and archival CDMA evidence handling — Law-enforcement extractions and archive normalization sometimes require maintaining the original CDMA-era container even when the source is a re-encoded MP4.

If your target is a GSM phone (AT&T, T-Mobile, most international carriers) instead of a CDMA one, convert MP4 to 3GP — the GSM-side cousin uses AMR-NB / AAC instead of EVRC / QCELP. For modern playback, MP4 stays MP4 — there's no need to convert it at all.

MP4 vs 3G2 — Format Comparison

Codec Choice for the 3G2 Output

Note: this converter uses AMR-NB or AAC-LC as the audio defaults for 3G2 output. The CDMA-native voice codecs in the 3GPP2 spec (EVRC, QCELP, SMV, VMR-WB) are decoded on the playback device — they're rare in encoder pipelines because their licensing was tied to CDMA carriers.

Frequently Asked Questions

Why is 3G2 separate from 3GP if the container is the same?

3GP came out April 2003 from the 3GPP (the GSM/UMTS standards body); 3G2 came out January 2004 from 3GPP2 (the CDMA2000 standards body). The container layout is the same MPEG-4 Part 12 base, but the audio codec lists diverge along carrier-network lines: GSM used AMR-NB / AMR-WB / AAC-LC, while CDMA2000 used EVRC / QCELP / SMV / VMR-WB. They were two different standards organizations writing very similar specs for two different cellular ecosystems.

Should I pick H.264 or H.263 inside the 3G2?

H.264 for almost everything — it's better quality per bit and works on every CDMA smartphone from roughly 2008 forward. Pin to Baseline or Main profile to stay safe on older firmware. H.263 only when targeting truly ancient CDMA feature phones (pre-2008 LG flips, early Razrs, BREW-based devices) where H.264 decoding is missing or buggy. MPEG-4 Part 2 for some mid-2000s embedded devices and signage hardware that sits between the two.

Why is my converted 3G2 so much smaller than the source MP4?

3G2 was designed for 64-384 kbps cellular bandwidth at 176x144 or 320x240 — orders of magnitude smaller than a 1080p MP4 at 5-10 Mbps. The default Quality Preset for 3G2 output drops bitrate to match the format's typical envelope. If your output looks too soft, raise the preset to Highest, increase the resolution preset, or set a Constant Bitrate manually. You're trading bitrate for legacy compatibility, which is the point of 3G2.

What audio codec should I pick for a 3G2 output?

AMR-NB for voice-only clips, MMS attachments, and the smallest possible files (narrowband 8 kHz, 4.75-12.2 kbps). AAC-LC for music or mixed audio that needs to actually sound listenable on modern hardware (64-256 kbps stereo). The 3G2 spec also formally supports EVRC, EVRC-B, EVRC-WB, 13K (QCELP), SMV, and VMR-WB — those are CDMA-native voice codecs decoded on Verizon/Sprint hardware but rarely used in encoder pipelines today.

Will Verizon and Sprint MMS still accept 3G2 in 2026?

Verizon's CDMA 1xRTT/EV-DO network was shut down December 31, 2022 and Sprint's legacy CDMA finished retiring on T-Mobile's network in 2022. MMS today goes over LTE / 5G as RCS or SMS-with-attachment; modern phones receive MP4 or even WebP / HEIC. 3G2 is now mainly useful for legacy device testing, archival restoration of pre-2010 phones, and emulator / kiosk fixtures — not for live MMS to consumer devices.

What's the maximum resolution 3G2 supports?

The container itself doesn't cap resolution — 3G2 is a wrapper around MPEG-4 Part 12, which supports anything H.264 supports including 1080p and 4K. In practice, 3G2 files are nearly always QCIF (176x144), QVGA (320x240), or CIF (352x288) because the format was tuned for 3G CDMA bandwidth. Encoding 1080p inside a 3G2 container is technically valid but will be rejected by every legacy CDMA player you'd actually want 3G2 for.

Can I trim or cut the MP4 while converting to 3G2?

Yes. Use the Trim section: select Time Range and enter start time + duration in seconds (12.5) or HH:MM:SS.sss (00:00:30.500). Trimming first means the encoder does less work and the output is smaller — useful when the target is an MMS attachment with a strict size cap.

Does the AAC audio in my MP4 transfer cleanly to 3G2?

AAC-LC re-encodes cleanly into 3G2 — pick AAC under Audio Codec to preserve music quality. Important caveat: the 3GPP2 spec explicitly excludes HE-AAC v2 and AMR-WB+, so if your MP4 used either, the converter re-encodes the audio (HE-AAC v2 -> AAC-LC by default, AMR-WB+ -> AMR-NB or AMR-WB). For voice-only sources, switching to AMR-NB produces the smallest 3G2 files and matches what legacy CDMA feature phones expect.

Can I batch convert a folder of MP4 files at once?

Yes. Drop in as many MP4 / M4V files as you want — entire folders work fine. They convert in parallel within your browser session and download individually or as a single ZIP. Settings can be applied uniformly (one quality preset and resolution for all 50 files) or tweaked per-file. Conversion happens in-browser, so the practical limit is your device's available memory, not a fixed cap.