Step 1: Share your 3GP files using the button above or by drag and drop.
Step 2: Click the 'Transform' button to start the transformation.
Step 3: Grab your converted WebM files.
3GP to WebM Transformation FAQ
How do I re-encode 3GP to WebM without losing video quality?
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Upload your 3GP file and the converter runs a CRF-based re-encode targeting visually-lossless WebM output (CRF 18 by default, lower values = larger file / higher quality). The codec is chosen to match the WebM container — H.264 for broad-compat MP4, H.265 for size-efficient MKV, VP9 for WebM, AV1 for newer pipelines. 3GP holds H.263 or MPEG-4 Part 2 video with AMR narrowband speech audio, all tuned for minimal bitrate rather than quality. WebM is deliberately narrow: VP8 or VP9 video (AV1 more recently) with Vorbis or Opus audio, and nothing else.
Can I add selectable subtitles once the file is WebM?
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Yes. 3GP has no usable soft-subtitle track, so subtitles for 3GP content had to be burned into the picture or shipped as a separate sidecar file. WebM carries subtitles as their own selectable stream, so after conversion you can attach an SRT track the viewer can switch on, switch off or restyle.
Will the WebM play in a browser when the 3GP would not?
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Yes, and that is usually the whole reason for the conversion. A 3GP embedded in a web page either shows a broken player or forces a download, because browsers ship no decoder for it. WebM plays inline through the native HTML5 video element with no plugin and no external application. WebM plays natively in every modern browser with no plugin, no licence fee and no patent exposure, which makes it the default for web-embedded video.
Both 3GP and WebM are modern containers — which should I actually keep?
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Keep whichever matches where the file is going, because neither is better in the abstract. One of these two is built for playback compatibility and the other for holding everything a file might contain, and they trade against each other exactly along that line. The pragmatic answer for most libraries is to archive in the feature-rich container and export to the compatible one on demand. 3GP files are tiny and decode on the weakest hardware imaginable, which is why feature phones and low-end handsets still record it.
Which video codec does the WebM output use?
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It depends on the WebM container. MP4 defaults to H.264 for the broadest playback support across phones, browsers, and Smart TVs. MKV defaults to H.265 / HEVC for roughly half the file size at equivalent quality. WebM defaults to VP9. The advanced options expose explicit codec choice if you need to override. WebM is a strict subset of Matroska that Google published in 2010 specifically to give HTML5 video a royalty-free container.
Will my audio track survive 3GP to WebM conversion?
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Yes. When 3GP and WebM share an audio codec (e.g. both carry AAC), audio is re-muxed with no re-encode — bit-identical. When the codecs differ, audio is transcoded to AAC / Opus / Vorbis depending on what the WebM container supports. Multi-track audio (commentary, alternate languages) is preserved.
Can I keep the original framerate when converting 3GP to WebM?
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By default yes — a 24fps 3GP stays 24fps in WebM; a 60fps 3GP stays 60fps. If you need to change rate (e.g. interlaced 29.97 → progressive 30, or 60 → 30 for upload limits), the framerate option handles 3:2 pulldown, deinterlacing, and frame-blending in the same encode pass.
How much will the file size change going from 3GP to WebM?
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Same-codec re-mux (3GP H.264 → WebM H.264 just changing container): nearly identical size. Codec change can swing dramatically: H.264 → H.265 typically halves the file at the same visual quality; VP9 is roughly comparable; AV1 cuts another 20-30% but is slower to encode.
Will the WebM file play on iPhone, Android, and Smart TVs?
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MP4 / H.264 plays natively on every modern device. MOV / H.264 plays on Apple devices and most TVs but not always on older Android. MKV needs VLC on iOS. WebM is browser-first. The advanced options include a "device compatibility" preset that picks the safest WebM codec / container for your target. WebM is a poor fit anywhere outside a browser — video editors, phones’ native galleries and Smart TVs largely ignore it.
How long does converting a 1-hour 3GP video to WebM take?
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Same-codec re-mux is near-instant — 30 to 60 seconds for a 1-hour file. A full codec re-encode runs at roughly 0.3-0.7x source duration on our GPU pipeline, so a 1-hour 3GP → WebM finishes in 18-40 minutes depending on resolution and target codec.
What is the maximum resolution supported for 3GP to WebM?
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Up to 8K (7680×4320) on Premium plans. Free conversions are capped at 4K (3840×2160) by the per-file size limit. HDR metadata (HDR10, HDR10+, Dolby Vision when present) is carried through where both 3GP and WebM containers support it.
Is my 3GP video private during conversion to WebM?
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Yes. Uploaded video files are processed in isolated workers, never viewed by a human, never indexed, and deleted within minutes of completion. The retention window is documented at /privacy/ and we publish no training corpus from user uploads.
