To play an MKV file on a Mac, use a video player that can read Matroska files and decode the tracks inside them. With Pro-Fi, you can open a local MKV from the file picker, drop it onto the player, or use File → Open Video.

This guide covers Pro-Fi on Apple silicon Macs running macOS 14 or later, including text subtitles and the controls you’ll use while watching.

Open your MKV file

  1. Install the Pro-Fi beta through TestFlight.
  2. Open Pro-Fi and choose Open video, or press Command-O.
  3. Select the .mkv file. You can also drop a local video file onto the player.
  4. Press Space to play or pause. Use the timeline to move to another part of the video.

For a file stored in the cloud, finish downloading it before checking local playback. Keeping a local copy makes it easier to distinguish a file issue from a slow connection.

Check the tracks inside the file

An MKV is a container: it can hold video, audio, subtitles, and other information together. The video codec is a separate part of the format. Matroska’s documentation describes how those streams fit inside the container.

Pro-Fi supports H.264, HEVC, and AV1 Main-profile video. AV1 support includes 8-bit and 10-bit sources. For audio, supported formats include AAC, AC-3, E-AC-3, DTS, FLAC, Opus, Vorbis, MP3, and PCM.

For an MKV with supported tracks, you can play the original file directly. You can compare its track formats with the Mac support list before deciding whether to change anything about the file.

Select an embedded subtitle track

An MKV can include subtitle tracks inside the file. While the video is open, go to Viewing options → Subtitles and choose an available text track.

Pro-Fi reads embedded SubRip, plain-text, WebVTT, and ASS subtitle tracks in local MKV files. These formats store text and timing information; Matroska also defines other subtitle types, as described in its subtitle format documentation.

If you’re checking a file’s subtitle support, the track’s format matters as much as its language. A track named “English” describes the language, while its codec identifies how the captions are stored.

Open a separate subtitle file

You can also open an external subtitle file from the Subtitles panel. Pro-Fi reads SRT and WebVTT files, plus the text in ASS and SSA files.

After opening subtitles, adjust their size and vertical position to suit your screen. Pro-Fi remembers those appearance settings across videos. A timing adjustment applies to the current session; a positive delay makes the captions appear later.

Pick a short exchange of dialogue when checking timing. Pause or seek back to the same line, make a small adjustment, and play it again. That gives you a consistent reference as you tune the delay.

Watch in fullscreen

Double-click the video or press Control-Command-F to enter native macOS fullscreen. Press Escape to return to the window.

The controls remain close to the video, and the main playback shortcuts work in the player window:

Key Action
Space Play or pause
Left / Right arrow Back or forward 15 seconds
Up / Down arrow Raise or lower volume
M Mute or restore sound
Command-comma Open Viewing options

These shortcuts are useful when you want to adjust playback without opening a settings panel. Subtitle controls remain available in fullscreen too.

Open a remote MKV

Choose File → Open Link, or press Command-L, to open a direct HTTPS media URL. Direct MKV playback uses servers with byte-range support so the player can read the part of the file you seek to. You can use a separate subtitle file with a remote stream.

Explore Pro-Fi for Mac for the current beta and playback features. If you also watch on a headset, our Apple Vision Pro MKV guide covers opening files and choosing the right video format there.