1단계: 파일을 업로드하세요 WebM 위 버튼을 사용하거나 드래그 앤 드롭으로 파일을 이동하세요.
2단계: '변환' 버튼을 클릭하여 변환을 시작하세요.
3단계: 변환된 파일을 다운로드하세요 MKV 파일
WebM 에 MKV 변환 FAQ
How do I convert WebM to MKV without re-encoding the video stream?
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When the WebM and MKV 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 MKV container and only the wrapper changes. A remux of a 1 GB WebM into MKV typically finishes in 5-15 seconds with zero quality loss.
Will multi-track audio survive WebM to MKV conversion?
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Yes — every audio track in the WebM (director commentary, alternate languages, descriptive audio) is preserved in the MKV 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.
Are subtitle tracks preserved when converting WebM to MKV?
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Soft subtitles (selectable tracks) survive when MKV 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 WebM to MKV keep chapter markers / DVD-style navigation?
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Chapter metadata transfers between WebM and MKV 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, so converting AVI to MKV produces an unchaptered file unless you add markers manually.
What about MKV attachments (fonts, cover art) when going WebM to MKV?
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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 WebM to MKV drops these attachments when MKV is not MKV — the elementary streams convert, but the attached payload stays in the source. Keep WebM as a backup if you depend on attached fonts.
Which codec does the MKV output use by default?
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The default codec is chosen to match the MKV 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.
How does HDR (HDR10, Dolby Vision) survive WebM to MKV?
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HDR static metadata (HDR10 mastering display values, max content light level) carries through to MKV 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 WebM commonly survives only into MKV with HEVC; converting to a MKV container that does not carry the DV layer flattens to HDR10.
Will the WebM to MKV converter keep variable framerate (VFR)?
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MKV and WebM record real per-frame timestamps and handle VFR natively, so WebM VFR survives into a MKV 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 WebM to 24 / 30 / 60 fps MKV for problematic targets.
Why is my MKV file smaller / larger than the WebM 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 WebM (Blu-ray rip) to a low-bitrate MKV (web upload) is the most common reason for a dramatic drop.
Does the WebM to MKV 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 WebM into MKV are limited by disk I/O, not CPU — a 30 GB WebM typically remuxes to MKV in under a minute regardless of resolution. Re-encodes scale with pixel count.
Is my WebM file private during MKV conversion?
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Yes — uploaded WebM files are processed in isolated workers and deleted within minutes of completion. We never view, store, retain, or share the content. See /privacy/ for the data retention window. The conversion pipeline runs on hardware we control end-to-end; no third-party APIs receive your file.
Can I trim, crop, or join WebM files during the MKV conversion?
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Not in the same job — keep conversion focused on container / codec. Use /trim/ to clip the WebM first, then queue the WebM -> MKV step. For joining several clips into one MKV, the /merge/ tool stitches them on a per-codec basis (it remuxes when the inputs share a codec, re-encodes otherwise) and emits a single MKV file at the end.