Filenary

Video Format Converter

Convert your video files between MP4 and WebM formats in your browser.

Drop your file here

or click to browse

Choose File

On first use, a ~30 MB conversion engine is downloaded to your browser (one time only).

This file is processed in your browser and never uploaded to a server.

How It Works

  1. 1. Drop your file here

  2. 2. Processing…

  3. 3. Download

Features

  • MP4 ⇄ WebM conversion
  • Processed inside your browser
  • No extra software needed

Frequently Asked Questions

Are large video files supported?
Yes, but processing time and memory use increase with file size depending on your device's power.
Do I need internet during processing?
Once the page loads, the conversion engine is downloaded to your device; the conversion itself can run in the browser without internet.
Which video formats can I convert between?
You can convert to MP4, WebM, MKV or AVI — each target format is re-encoded with a matching video and audio codec (e.g. H.264 for MP4, VP8 for WebM).
Will converting reduce my video quality?
Since the video is fully re-encoded rather than copied, there's some quality loss inherent to any transcode, though it's usually not noticeable at normal viewing sizes.
Why does the first conversion take longer to start?
The FFmpeg engine only needs to load into your browser tab once per session — after that first few-second delay, later conversions on the same page start immediately.

Related Tools

Add this tool to your website

Copy the code below and paste it into any page. It's free, needs no sign-up, and files are processed in your visitors' own browsers.