How do I re-encode MP4 to 3GP without quality loss?
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Upload your MP4 file and our converter applies a CRF-based re-encode targeting visually-lossless 3GP output (CRF 18 by default, lower = larger / higher quality). The codec is chosen to match the 3GP container (H.264 / H.265 / VP9 / AV1 as appropriate).
Will my audio track survive MP4 to 3GP conversion?
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Yes — audio is re-muxed (when MP4 and 3GP share an audio codec) or re-encoded to AAC / Opus / Vorbis depending on what the 3GP container supports. Multi-track audio (commentary, alternate languages) is preserved.
Can I keep the original framerate when converting MP4 to 3GP?
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By default, framerate is unchanged (MP4 24fps stays 24fps in 3GP). If you need to change it (e.g. interlaced 29.97 → progressive 30fps), use the framerate option, which handles 3:2 pulldown and deinterlacing in the same pass.
What is the file size difference between MP4 and 3GP?
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Same-codec re-muxes (e.g. MP4 → 3GP where both use H.264) produce nearly-identical sizes. Codec changes can swing the size dramatically: H.264 → H.265 typically halves the file at the same visual quality; H.264 → VP9 is roughly comparable.
iPhone / Android / Smart TV 上的3GP文件会播放吗?
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MP4 / H 264 在各地的本地游戏。 MOV / H 264 在苹果设备和大多数智能电视上玩, 但不在老的Android上玩。 MKV 在iOS上需要 VLC。 高级选项包括“ 设备兼容性” 预设, 选择目标设备的最安全编码/ 容器组合 。
How long does converting a 1-hour MP4 file to 3GP take?
What is the max resolution supported for MP4 to 3GP?
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Up to 8K (7680×4320) on Premium. Free users are capped at 4K (3840×2160) per the file-size limit. HDR metadata (HDR10, Dolby Vision) is preserved where both MP4 and 3GP containers support it.
Is my MP4 video private during conversion?
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是的——上传视频文件由孤立的工人处理,并在完成后几分钟内删除,我们从不查看、储存、保留或分享内容。
Can I crop or trim during the MP4 to 3GP conversion?
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Not in the same step — use /video-trim/ or /video-cutter/ to trim before converting, then queue the MP4 → 3GP step. Trimming and converting in series is faster than re-encoding the whole file just to crop.
Why is the 3GP file blurry / pixelated compared to the MP4 source?
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Almost always a bitrate-too-low setting. Re-encoding from a high-bitrate MP4 into a lower-bitrate 3GP at the default CRF compresses heavily on motion-heavy scenes. Push CRF down to 16-18 (or set explicit bitrate) and re-run to recover quality.
Does the MP4 to 3GP converter support subtitles?
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Yes — embedded subtitle tracks (mov_text in MP4, SRT/ASS in MKV) are preserved when both MP4 and 3GP containers support them. Burned-in (hardsub) subtitles transfer automatically because they are part of the video frame.