We re-package or re-encode your MP4 into the 3GP container. When the codec matches, we copy streams (fast, lossless); when it does not, we re-encode with H.264 / H.265 / VP9 at a high default quality.
Is converting MP4 to 3GP lossy?
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If the codec inside MP4 is compatible with 3GP, the conversion is a remux (no quality loss). If we need to re-encode, the default CRF setting is visually lossless for typical viewing distances.
Yes when 3GP supports them (MP4, MKV, MOV). All audio tracks, languages, and embedded subtitles are kept. For single-track containers (3GP, FLV), only the default track survives.
How big can my MP4 file be?
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Free accounts have a size limit that varies by file type; PRO accounts allow much larger files. For very large MP4 files we recommend the PRO plan or pre-trimming with our video-trim tool.
What codec is used inside the 3GP output?
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We pick the best-supported codec for the 3GP container — H.264 for MP4 / MOV / FLV, VP9 for WebM, AV1 when targeting modern web, H.265 when 3GP supports it. You can override in the options panel.
转换器能改变框架率吗?
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是的,选择小组暴露了目标框架费率(24、25、30、60),默认情况下,我们保留源框架费率。
Will my converted 3GP play on TV, phone, and browser?
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Yes. Our default profile targets universal playback — H.264 + AAC inside 3GP works on every major platform, browser, and smart TV from the last decade.
Is the MP4 to 3GP converter free?
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Yes, within the free size limit. PRO unlocks larger files, GPU-accelerated transcoding, and 4K output.
Does PDF.to support 4K and HDR MP4 files?
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Yes. 4K is preserved by default; downscale via the options panel if needed. HDR is preserved when 3GP supports it (MKV, MP4 with HEVC) or tonemapped to SDR when targeting older formats.
