Slimvid

Free Online Video Converter

Convert MP4, MOV, MKV and WebM on your device. No upload.

Drop videos here, or click to browse

Up to 1GB each · MP4, MOV, WebM or MKV

Choose files

Processed locally in your browser. Nothing is uploaded.

Settings

Add a video and the settings for this tool appear here.

How it works

  1. 1Drop the video you want to convert.
  2. 2Choose an output format. MP4 (H.264) is the safest choice for sharing and playback.
  3. 3Convert and download. Your original file is untouched.

Processed locally in your browser. Nothing is uploaded.

Three steps

How to convert a video

No sign-up, no upload queue, no watermark. Everything happens on your device.

  1. 1

    Drop your file

    Drop the video you want to convert.

  2. 2

    Choose settings

    Choose an output format. MP4 (H.264) is the safest choice for sharing and playback.

  3. 3

    Download

    Convert and download. Your original file is untouched.

Same job, other limits

Related size and platform pages

Convert MOV to MP4 OnlineTurn iPhone and camera MOV files into an MP4 that plays in browsers, chat apps and slides.MOV to MP4Convert MKV to MP4 OnlineRemux an MKV into MP4 so phones, editors and chat apps will play it.MKV to MP4Convert WebM to MP4 OnlineTurn browser recordings into MP4 for iPhone, editors and chat apps.WebM to MP4Convert MP4 to WebM OnlineMake a WebM from an MP4 when a site or HTML5 player asks for one.MP4 to WebM

Keep going

Related tools

FAQ

Video Converter FAQ

Which output formats are available?
MP4 (H.264 + AAC), WebM (VP9 + Opus), MOV, MKV and AVI. MP4 plays on every phone, browser and TV; WebM is smaller for the web.
Does converting reduce quality?
Re-encoding always involves some loss, but we use quality-based encoding that keeps the result visually indistinguishable from the source for normal footage.
Can I convert without re-encoding?
When the source codec is already compatible with the target container (for example H.264 in MKV to MP4), the tool copies the streams for an instant, lossless conversion.
Is there a file size limit?
Process videos up to 1GB on your device. Nothing is uploaded. The desktop app is in development. Join the waitlist for launch updates.

Desktop · Coming soon

Desktop · Coming soon

The desktop app is in development. Join the waitlist for launch updates.

Get early accessCompare web vs desktop
  • No file size limit — 4K, hour-long recordings, anything
  • Batch queues: drop a folder, apply one preset
  • Hardware-accelerated encoding (H.264 / H.265)
  • Works fully offline, same privacy guarantee