How to Convert Video Formats (MOV, MP4, WEBM) — Free

An iPhone .mov clip that won't upload where you need it, an MP4 you want as WEBM for a smaller web-friendly file — here's how to convert between video formats in your browser, no software to install.

Steps

  1. Upload your video at Stelluna's Video Format Converter — MP4, MOV, WEBM, MKV, or AVI, up to 300MB.
  2. Pick the format you want — MP4, MOV, or WEBM.
  3. Click Convert. Your video is converted right there in your browser using your device's own hardware video encoder.
  4. Download the converted file.

Ready to try it? Free, no sign-up, your video never leaves your device.

Open Video Format Converter

Which format should I actually use?

FormatBest for
MP4Maximum compatibility — every device, app, and platform accepts it
MOVApple's native format — best when staying inside the Apple ecosystem (Final Cut, iMovie)
WEBMSmaller file size, built for web use — ideal for embedding on a website

Most "why won't this video upload" problems on non-Apple platforms come down to MOV — converting to MP4 almost always fixes it.

FAQ

How do I convert MOV to MP4?

Upload the MOV file at Stelluna's Video Format Converter, choose MP4 as the target format, and click Convert.

Is it free?

Yes — no account, no watermark, no limit on how many videos you convert.

Does my video get uploaded anywhere?

No. The conversion happens entirely in your browser, using your device's own video encoder — your video never leaves your device.

How long does it take?

Depends on the video's length and resolution — most short clips convert in a few seconds to a minute, right in the browser tab.

Is there a file size limit?

Yes, up to 300MB, to keep the conversion running smoothly in your browser.