We re-package or re-encode your 3GP into the MP4 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 3GP to MP4 lossy?
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If the codec inside 3GP is compatible with MP4, 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.
What resolution will my MP4 output have?
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Source resolution by default. The options panel lets you downscale to 1080p, 720p, 480p, or pick a custom size — useful for shrinking files for sharing or upload.
Does the converter preserve audio tracks and subtitles?
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Yes when MP4 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 3GP file be?
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Free accounts: 100 MB. PRO accounts: 5 GB. For very large 3GP files we recommend the PRO plan or pre-trimming with our video-trim tool.
What codec is used inside the MP4 output?
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We pick the best-supported codec for the MP4 container — H.264 for MP4 / MOV / FLV, VP9 for WebM, AV1 when targeting modern web, H.265 when MP4 supports it. You can override in the options panel.
Can the converter change frame rate?
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Yes. The options panel exposes target frame rates (24, 25, 30, 60). By default we preserve the source frame rate.
Will my converted MP4 play on TV, phone, and browser?
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Yes. Our default profile targets universal playback — H.264 + AAC inside MP4 works on every major platform, browser, and smart TV from the last decade.
Is the 3GP to MP4 converter free?
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Yes for files under 100 MB. PRO unlocks larger files, GPU-accelerated transcoding, and 4K output.
Does PDF.to support 4K and HDR 3GP files?
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Yes. 4K is preserved by default; downscale via the options panel if needed. HDR is preserved when MP4 supports it (MKV, MP4 with HEVC) or tonemapped to SDR when targeting older formats.
How long does a 3GP to MP4 conversion take?
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Stream-copy (compatible codec) finishes near disk speed — a 1 GB file in well under a minute. Re-encoding scales with resolution and length; expect roughly real-time for 1080p on the free plan, faster on PRO.
Do you keep my 3GP video?
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No. The 3GP upload and MP4 output are deleted within an hour. Conversion happens in an isolated worker with no content logging.