Does MKV to MP3 keep the video?

MKV (Matroska) is an open container that can hold virtually any codec combination — video in H.264/H.265/VP9/AV1 with audio in AAC, AC-3, DTS, FLAC, Vorbis, Opus, or PCM, often several tracks at once. Converting MKV to MP3 discards all video and subtitle streams and encodes the default audio track to MP3.

Because MKV audio can be anything, the conversion path adapts: lossless tracks (FLAC, PCM) give a first-generation MP3 encode; lossy tracks (AAC, AC-3, DTS) are transcoded, where a 192 kbps+ output keeps stacking artefacts inaudible. Surround tracks (5.1 AC-3/DTS) are downmixed to stereo automatically, since MP3 is a stereo/mono format.

MKVs frequently contain multiple audio tracks — different languages, commentary, or stereo/surround alternatives. This tool extracts the default (first) track. If you need a specific alternate track, remux the MKV in a desktop tool first so the desired track is the default.

Reasons to convert MKV to MP3 usually come down to compatibility, file-size, or specific feature requirements. Common situations:

• An app or platform only accepts MP3 uploads.
• You need a feature unique to MP3 (e.g. lossless editing, chapter markers, smaller streaming size, etc.) that MKV doesn't provide.
• You're optimising file size — modern formats often produce smaller files than the older format you started with.
• You need a single archival format across a project so files behave consistently in the same viewer.

1. Open the MKV → MP3 tool on mp3.now.
2. Drag your MKV file onto the drop zone, or click Select files. You can drop a whole folder of files at once.
3. The output is fixed to MP3. If the format supports extra options (bitrate, sample rate, channels, volume normalization), tweak them in the options panel.
4. Click Convert. The job runs on our server and finishes in a few seconds for typical tracks.
5. Download the result. Files stay in storage for 24 hours and are then permanently deleted.

The entire flow is free for the first 10 jobs per day with no signup required. A free account doubles that quota; a premium plan removes the limit entirely.

• Multi-track MKVs: the default/first audio track is the one extracted.
• 5.1 surround audio is downmixed to stereo — normal and expected for MP3 output.
• If the MKV audio is FLAC or PCM, 320 kbps output is a clean first-generation encode.
• Dialogue in downmixed film audio can sit low; run the result through Normalize MP3 to bring levels up.
• Long files convert quickly — only the audio stream is processed, never the video.