MKV to HEVC Converter

Convert MKV to HEVC: What This Tool Actually Produces

This tool decodes the video track inside your MKV and re-encodes it with H.265 (HEVC), the codec built to reach H.264-equivalent quality at roughly 25-50% lower bitrate. One thing to understand before you start: .hevc is a codec name, not a normal container, so to keep a soundtrack this converter wraps the H.265 video in a Matroska container and simply gives the file a .hevc extension. The output therefore carries your audio (re-encoded to AAC by default) and opens in VLC, mpv, and other FFmpeg-based players — but the .hevc extension itself is non-standard, so phones, TVs, and QuickTime may not recognize it by name. Because MKV is already a Matroska container that holds H.265 natively, most people are better served converting to MKV to MP4 or MKV to MKV with the codec set to H.265 — same codec, same size savings, a normal extension. Either way this is a re-encode, not a lossless remux: the picture is decoded and transcoded to a fresh H.265 stream rather than copied.

How to Convert MKV to HEVC

1. Upload Your MKV File: Drag and drop your .mkv onto the page or click "+ Add Files." You can queue several files and convert them in one batch with the same settings.
2. Set the Quality Preset or Rate-Control Mode: The video codec is fixed to H.265 for .hevc output. Leave Quality Preset on "Very High (Recommended)" for a one-click result, or open File Compression and choose Constant Quality (a CRF-style perceptual target), Constant Bitrate, Variable Bitrate, or Specific file size.
3. Adjust Resolution, Audio Codec, or Trim (Optional): Use Video resolution to keep the original frame or downscale it, switch the Audio Codec (AAC by default; AC3 and MP3 are also offered), or set a Time Range under Trim to export only part of the clip.
4. Convert and Download: Click "Convert" and download the file. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark.

What the .hevc File Actually Is

The .hevc extension is ambiguous: a raw encoder emits a bare video-only elementary stream under that name, while this converter produces a Matroska-wrapped file so your audio survives. Because MKV can hold many tracks but a re-encode keeps only one, a multi-track MKV comes out with a single audio track and no subtitle or chapter tracks. This table shows the three things people mean by "HEVC" and which one you get here.

Walk-through: Choosing a Rate-Control Mode

The File Compression section decides how the encoder spends bits. Match the mode to your goal:

• For a predictable quality level, use Constant Quality. It targets a perceptual quality rather than a size, so the encoder spends more bits on complex scenes and fewer on simple ones. Lower values mean higher quality and a larger file; higher values do the reverse. This is the mode for "looks the same, just smaller."
• For a predictable bitrate — feeding a streaming or muxing pipeline — pick Constant Bitrate or Variable Bitrate and enter the target in Mbps.
• For a hard size cap, use Specific file size and name a target in MB; the encoder scales toward it. Combining an aggressive size target with a resolution downscale is where visible quality loss shows up first, so change one variable at a time.

If the MKV you upload already holds an H.265 video track, this tool still routes it through a full decode and re-encode rather than copying the stream untouched, so plan for some processing time and pick a quality mode rather than assuming a lossless pass-through.

MKV vs HEVC at a Glance

MKV is a container; HEVC is a codec — so "MKV to HEVC" really means "re-encode the video inside this container to H.265." MKV can already hold H.265, which is why this conversion is a transcode rather than a simple repackage.

Common Errors and How to Fix Them

• "My phone / TV / QuickTime won't open the .hevc file" — Those players recognize files by extension and don't expect .hevc. The data inside is standard Matroska + H.265, so rename it to .mkv, or better, convert to MKV to MP4 with H.265 selected for a file that plays as-is.
• "The output has no sound" — Check the Audio Codec was left on (AAC by default). If the source MKV's primary audio track was missing, or you disabled the audio codec, the output won't have a soundtrack.
• "My second audio track or subtitles are gone" — Expected. This converter re-encodes to a single audio track and does not carry subtitle or chapter tracks, whichever output format you pick. To keep every track from a multi-track MKV, use a desktop remuxer such as MKVToolNix or FFmpeg (ffmpeg -i in.mkv -map 0 -c copy out.mkv), which copies all tracks without re-encoding.
• "H.265 isn't supported on the playback device" — Older hardware lacks an HEVC decoder. Convert to H.264 in an MP4 container for the widest compatibility instead.
• "Output looks heavily pixelated" — You likely paired a small Specific file size target with a resolution downscale. Raise the size target or keep the original resolution.

When This Doesn't Work

DRM-protected or corrupted MKV files can't be re-encoded — the converter needs a readable video stream. A multi-track MKV comes out with only its primary video plus a single audio track, so a file with several audio languages or subtitle tracks won't round-trip every track; keep those with a desktop remuxer instead. And if what you actually want is a shareable, universally playable H.265 video rather than a .hevc-named file, skip this page and use MKV to MP4 or MKV to MKV with the H.265 codec selected — MKV holds H.265 natively, and the .hevc output is itself a Matroska file under a nonstandard name, so there is no reason to give it that extension unless a tool asks for it. If your source is long and you only need a slice, trim the MKV first, then convert the short clip.

Frequently Asked Questions

Does the .hevc file this tool makes have audio?

Yes. Although a raw .hevc from an encoder is video-only, this converter wraps the H.265 video in a Matroska container so it can carry a soundtrack, then gives the file a .hevc extension. Your audio is re-encoded to AAC by default (AC3 and MP3 are also available). If the output is silent, either the Audio Codec was turned off or the source MKV's primary track had no audio to begin with.

Why won't my phone or TV open the .hevc file?

Most consumer players decide what a file is from its extension, and they don't expect .hevc. The bytes inside are a standard Matroska stream, so VLC and mpv play it fine, and you can rename the file to .mkv to make other players accept it. For a file that opens everywhere without renaming, convert to MKV to MP4 or MKV to MKV with H.265 selected.

What happens to my extra audio tracks and subtitles?

A multi-track MKV comes out with a single audio track and no subtitle or chapter tracks — the re-encode maps the primary video plus one audio track into the output. If you need to keep several audio languages or subtitle tracks, that is a remux job better handled by a desktop tool such as MKVToolNix or FFmpeg (ffmpeg -i in.mkv -map 0 -c copy out.mkv), which copies every track without re-encoding.

My MKV is already H.265 — does this just copy the stream?

No. This page is a converter, not a remux: it decodes the MKV's video and re-encodes it to a fresh H.265 stream rather than copying the existing one bit-for-bit, so expect a quality mode to apply and some encoding time. If your only goal is to pull the existing H.265 video out of the MKV untouched, use FFmpeg to remux (ffmpeg -i in.mkv -map 0:v:0 -c copy out.hevc) rather than this re-encoder.

Is HEVC really about half the size of H.264?

Roughly, at the same visual quality. The HEVC standard (ITU-T H.265 / ISO/IEC 23008-2, approved 2013) was designed for 25-50% better compression than H.264/AVC; a formal subjective study measured about a 49% bitrate reduction, and savings tend to be larger at 4K than at lower resolutions. In our testing, a 1080p MKV re-encoded to H.265 at the "Very High" preset came out visibly smaller than the same clip encoded to H.264, though the exact ratio depends on the footage.

Why is MKV a container while HEVC is a codec?

MKV (Matroska) is an open container standard — standardized as IETF RFC 9559 in 2024 — that wraps one or more video, audio, and subtitle streams plus chapters into a single file but does no compression itself. HEVC (H.265) is a video codec, the algorithm that compresses the picture. So an MKV can already contain HEVC video; "MKV to HEVC" only makes sense as re-encoding the video to H.265 (what this tool does) or extracting it as a stream.

Should I convert MKV to a .hevc file or to MP4/MKV with H.265?

For almost everyone, MP4 or MKV. You get the same H.265 codec and size savings plus a normal extension that plays on modern phones, TVs, and browsers, and the audio is kept. Choose the .hevc output only when a specific downstream tool asks for a file with that exact name. Use MKV to MP4 for the most compatible result or MKV to MKV to stay in a flexible container.

Do I need a special player or license to watch HEVC?

To play HEVC you need an HEVC decoder. VLC and mpv include one on every desktop OS; on Windows 10 and 11 the built-in player needs Microsoft's "HEVC Video Extensions" from the Store, and Apple devices have decoded HEVC since 2017. If a device can't decode H.265 at all, re-encode to H.264 in MP4 for the widest reach.

Are my uploaded files kept after conversion?

No. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically a few hours after conversion. There is no sign-up, no watermark, and your files are never shared or made public.