Format Conversion — Convert HLS & DASH Streams to MP4, MKV, MOV

Convert HLS and DASH streams into standard video containers, or pull out the audio track as MP3 or AAC. All processing happens locally via WebAssembly.

Format conversion is a Professional feature. Upgrade your plan to unlock it.

Video Downloader Plus can remux HLS (m3u8) and DASH (mpd) streams into standard video containers and extract audio tracks into standalone audio files. Conversion runs entirely inside your browser — nothing is uploaded to a server.

Video conversion targets

Target format	Best for
MP4	Broadest device and browser compatibility — the safe default for most use cases
MKV	Archiving with multiple audio tracks, multiple subtitle tracks, and rich metadata
MOV	Editing in Final Cut Pro or working within the Apple ecosystem
WebM	Embedding on web pages and open-format workflows

Audio extraction targets

Target format	Best for
MP3	Maximum compatibility across every audio player and platform
AAC	Better quality-to-size ratio, especially for Apple devices and services

How conversion works

1. Detect the stream

   Video Downloader Plus identifies an HLS or DASH stream on the page and surfaces it in the popup.

2. Choose a target format

   Select your desired output format from the format picker before starting the download.

3. Local processing via WebAssembly

   Video Downloader Plus downloads all segments and passes them through a WebAssembly-based media engine running in your browser. No data leaves your device during this step.

4. Save the output file

   The finished file is written to your downloads folder in the format you selected.

Format comparison

	MP4	MKV	MOV	WebM
Device compatibility	Universal	Good (VLC, most players)	Apple ecosystem	Browsers, Linux
Multiple audio tracks	Limited	Excellent	Good	Limited
Subtitle support	Basic	Excellent (SRT, ASS, PGS)	Good	Basic (WebVTT)
File size	Medium	Medium	Medium–Large	Smaller
Streaming friendly	Excellent	Poor	Good	Good
Professional editing	Good	Limited	Excellent (Final Cut)	Limited
Web embedding	Good	Not recommended	Not recommended	Excellent

When to use each format

• MP4 — The right choice for almost everything. Works on every phone, TV, tablet, and browser without configuration.
• MKV — When you want to preserve alternate language tracks, multiple subtitle files, or attach metadata for a media server like Plex or Jellyfin.
• MOV — When the file is headed into Final Cut Pro or another Apple editing tool that handles MOV natively.
• WebM — When file size matters and the destination is a browser or Linux environment. Also the format to reach for when you want VP9 or AV1 output.

Audio format comparison

	MP3	AAC
Compatibility	Universal	Excellent on all modern devices
Quality at low bitrates	Adequate	Noticeably better
File size at equivalent quality	Larger	Smaller
Best for	Broadest reach, legacy players	Higher fidelity, Apple ecosystem

Key details

• Local-only processing — The WebAssembly media engine runs entirely in your browser. Your video data stays on your machine.
• Lossless quality — Video Downloader Plus remuxes streams into the target container without re-encoding video or audio, so there is no quality degradation for supported codec combinations.
• Automatic track muxing — HLS and DASH streams with separate audio and video renditions are merged into a single output file before being saved.
• DASH SegmentBase passthrough — When a DASH stream uses SegmentBase (meaning the content is already a standard MP4 with byte-range requests), Video Downloader Plus downloads the file directly and skips the conversion step entirely.