Step 1: Provide your MP4 files using the button above or by toss and let go.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Fetch your converted HLS files.
MP4 to HLS Conversion FAQ
How do I convert MP4 to HLS without re-encoding the video stream?
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When the MP4 and HLS containers can both carry the same codec (H.264, H.265, VP9, AV1), the converter falls back to a remux: the elementary streams are copied byte-for-byte into the HLS container and only the wrapper changes. A remux of a 1 GB MP4 into HLS typically finishes in 5-15 seconds with zero quality loss. Almost every MP4 in the wild is H.264 video with AAC audio; the container also legally holds HEVC, AV1 and VP9. 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 MP4. 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.
Will multi-track audio survive MP4 to HLS conversion?
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Yes — every audio track in the MP4 (director commentary, alternate languages, descriptive audio) is preserved in the HLS when the target container supports multi-stream audio. MKV and MOV handle unlimited audio tracks; MP4 supports many but some hardware players only see track 1; WebM is capped at one Opus / Vorbis track. HLS is Apple’s HTTP Live Streaming — not a file but a playlist plus a folder of short media segments.
Are subtitle tracks preserved when converting MP4 to HLS?
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Soft subtitles (selectable tracks) survive when HLS can carry them: MKV holds SRT, ASS, SSA, PGS, VobSub natively; MP4 only holds mov_text (a stripped-down format). Converting an MKV with ASS styled subs to MP4 will typically downgrade them to mov_text or burn them in. Hardsubs (burned into the video) carry over regardless.
Does MP4 to HLS keep chapter markers / DVD-style navigation?
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Chapter metadata transfers between MP4 and HLS whenever both containers support a chapter atom (MKV, MP4, MOV). WebM stores chapters in a Matroska-compatible block, so MKV <-> WebM chapters round-trip cleanly. AVI has no chapter spec at all, so an AVI source arrives with no chapters to carry across and an AVI target cannot store the ones it was handed; add markers manually afterwards if you need them.
What about MKV attachments (fonts, cover art) when going MP4 to HLS?
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MKV is the only mainstream container that stores arbitrary attached files (TTF fonts for ASS subs, JPG cover art, fan-translated PDF inserts). Going from MP4 to HLS drops these attachments when HLS is not MKV — the elementary streams convert, but the attached payload stays in the source. Keep MP4 as a backup if you depend on attached fonts.
Which codec does the HLS output use by default?
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The default codec is chosen to match the HLS container conservatively: MKV defaults to H.265 (HEVC) for better compression; MP4 defaults to H.264 for the widest device support; WebM defaults to VP9; AVI uses MPEG-4 ASP (DivX/Xvid lineage). Override via the advanced codec dropdown — AV1 is available for MKV / WebM where you want maximum compression and can wait through the encode. HLS is not a single downloadable file — to keep it offline it has to be muxed back into a normal container first.
How does HDR (HDR10, Dolby Vision) survive MP4 to HLS?
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HDR static metadata (HDR10 mastering display values, max content light level) carries through to HLS when both containers and the chosen codec support it (HEVC, AV1 in MKV / MP4). Dolby Vision is more fragile — DV profile 5 / 7 / 8.1 in MP4 commonly survives only into MKV with HEVC; converting to an HLS container that does not carry the DV layer flattens to HDR10.
Will the MP4 to HLS converter keep variable framerate (VFR)?
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MKV and WebM record real per-frame timestamps and handle VFR natively, so MP4 VFR survives into an HLS of those formats with no resampling. MP4 nominally stores timestamps too but some players assume CFR; the converter exposes a "force CFR" toggle that resamples VFR MP4 to 24 / 30 / 60 fps HLS for problematic targets.
Why is my HLS file smaller / larger than the MP4 after conversion?
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Same-codec remux produces a near-identical size (container overhead differs by 0.1-2%). A codec change can swing the size by 50% or more: H.264 to H.265 typically halves the file at the same visual quality; H.264 to AV1 halves it again on a slow preset. Going from a high-bitrate MP4 (Blu-ray rip) to a low-bitrate HLS (web upload) is the most common reason for a dramatic drop.
Does the MP4 to HLS converter handle 4K / 8K / 60fps content?
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Yes up to 8K (7680x4320) on Premium. Free tier handles 4K (3840x2160) up to the 1 GB file cap. Pure remuxes (same-codec passthrough) of large MP4 into HLS are limited by disk I/O, not CPU — a 30 GB MP4 typically remuxes to HLS in under a minute regardless of resolution. Re-encodes scale with pixel count.
