Step 1: Share your WebM 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 HLS files.
WebM to HLS Transformation FAQ
How do I re-encode WebM to HLS without losing video quality?
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Upload your WebM file and the converter runs a CRF-based re-encode targeting visually-lossless HLS output (CRF 18 by default, lower values = larger file / higher quality). The codec is chosen to match the HLS container — H.264 for broad-compat MP4, H.265 for size-efficient MKV, VP9 for WebM, AV1 for newer pipelines. WebM is deliberately narrow: VP8 or VP9 video (AV1 more recently) with Vorbis or Opus audio, and nothing else. An HLS stream is an .m3u8 manifest pointing at a ladder of H.264 or HEVC segments at several bitrates, so the player can switch quality mid-playback.
Can the HLS hold more than one audio track?
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Yes, and it is a real upgrade over WebM. HLS treats every audio stream as a first-class track, so an original-language mix, a dub and a director commentary can live in one file with the player switching between them on demand. HLS adapts to the viewer’s bandwidth in real time and is the only streaming format Safari and iOS support natively.
Is HLS a container or a codec, and does that change what I get back?
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It changes what to expect from the output file. One side of this conversion names an encoding rather than a wrapper, so what comes back is that bitstream inside whichever container suits it best — normally MP4 or MKV. The extension reflects the container; the codec is what actually determined the file size and where it will play.
Which video codec does the HLS output use?
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It depends on the HLS 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. HLS is Apple’s HTTP Live Streaming — not a file but a playlist plus a folder of short media segments.
Will my audio track survive WebM to HLS conversion?
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Yes. When WebM and HLS 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 HLS container supports. Multi-track audio (commentary, alternate languages) is preserved.
Can I keep the original framerate when converting WebM to HLS?
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By default yes — a 24fps WebM stays 24fps in HLS; a 60fps WebM 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 WebM to HLS?
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Same-codec re-mux (WebM H.264 → HLS 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 HLS 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 HLS codec / container for your target. HLS is not a single downloadable file — to keep it offline it has to be muxed back into a normal container first.
How long does converting a 1-hour WebM video to HLS 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 WebM → HLS finishes in 18-40 minutes depending on resolution and target codec.
What is the maximum resolution supported for WebM to HLS?
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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 WebM and HLS containers support it.
Is my WebM video private during conversion to HLS?
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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.
Can I crop, trim, or rotate during the WebM to HLS conversion?
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Not in the same step — use /video-trim/ or /video-cutter/ to clip first, then run the WebM → HLS conversion. Chaining trim and convert is faster than re-encoding the entire WebM just to drop unused footage.
HLS (HTTP Live Streaming) is a streaming protocol developed by Apple for delivering audio and video content over the internet. It provides adaptive streaming for better playback performance.
