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Batch Convert Videos to MP4, MKV, WEBM or MOV — Locally

VidFabs converts up to 20 videos at once and repackages losslessly whenever possible, all on your own machine.

Most format converters make you choose between two bad options: upload your footage to some website and wait, or re-encode everything and lose quality on files that didn’t need it. VidFabs’ Format converter does neither. It runs entirely on your machine, handles up to 20 files per batch, and — this is the important part — it repackages losslessly whenever it can, and only re-encodes when it truly has to.

Why convert locally

Nothing leaves your device. There’s no upload progress bar, no queue behind other users, no size cap imposed by a web service, and no privacy question about where your video sits after you’re done. A bundled FFmpeg engine does the work at the speed of your CPU, and your files stay exactly where they are.

Step by step

Format converter

  1. Open Toolbox → Format converter.
  2. Drag in files — up to 20 per batch — or click Add files.
  3. Pick the target format: MP4, MKV, WEBM or MOV. Each row shows the file’s duration, its codec, and the mode the converter will use.
  4. Click Start convert. Rows show live status and an ETA, and you can cancel any time.
  5. When a file finishes, Open folder jumps straight to the output. Results also land in My Files → Edited.

The Toolbox groups this alongside eleven other single-purpose batch tools, each with the same live-ETA, cancel-anytime workflow.

The Toolbox

The part that saves your quality: remux vs re-encode

Here’s what makes this converter different. For every file, it inspects the streams and tells you before you start which of two modes it will use:

  • Will repackage (fast). The codecs already fit the target container, so the file is rewrapped without touching the video data at all. It’s lossless and near-instant — a two-second operation even on a large file.
  • Will re-encode. The codecs don’t fit the target container — say VP9 into MP4, or an H.264 file into WEBM — so VidFabs transcodes (to H.264/AAC, or VP9/Opus for WEBM).

Because the mode is shown up front on each row, you always know whether a conversion is a quick lossless rewrap or a real encode. No surprises, and no re-compressing a file that only needed a new wrapper.

Handy details

  • MP4 output is written with faststart, so it begins playing immediately when streamed from a web server.
  • Files the app can’t probe — corrupt or genuinely unsupported — are flagged individually instead of silently failing the whole batch.
  • Typical jobs: rewrap MKV or MOV footage to MP4 so it plays everywhere (losslessly), produce WEBM for web embedding, or normalize a mixed folder of downloads into one consistent format.

The full reference is in the Format Converter guide.

Get VidFabs

VidFabs is free on Windows 10 / 11 (64-bit) and needs no GPU — all twelve toolbox tools, including the converter, are included at no cost.

Download VidFabs for Windows — the macOS build is coming soon.