EditDuckРусский

Convert WebM to MP4

Screen recorders and websites save WebM, which iPhones, messengers and many editors won’t take. Re-save it as an MP4 that opens everywhere. The recording stays yours: it is not sent to a server or stored.

WebM files only · other formats open in “Convert to MP4”

Your privacy comes first

Your contracts, passport scans and family videos stay yours. No one but you gets to see them.

  • We never store your files

    They don’t even reach us: your phone or computer does the work. Nothing to delete later.

  • 100% free

    No daily limits, no file-size cap, no paid Pro plan.

  • No sign-up

    No account to create, no email to give. No account, nothing to hack.

How it works

  1. Open the WebMA screen recording, a clip saved from a website or a call recording. Only WebM files are taken here.
  2. Check the sizeThe panel shows the expected MP4 size. Under the gear you can lower the picture to 1080p, 720p or 480p.
  3. Save the MP4Keep the tab open while it works: the picture is re-saved frame by frame.

Why WebM to MP4 means re-saving

WebM is the web’s own video format. Screen recorders that run in a tab, many online meeting tools and sites like Wikipedia use it. Inside there is VP8, VP9 or AV1 picture and Opus sound, and MP4 players expect H.264 and AAC instead. So, unlike MKV or MOV, a WebM can’t simply be repacked: both picture and sound are encoded again.

What you get

  • H.264 picture and AAC sound: the pair every phone, TV, messenger and editor plays.
  • The same frame size, rounded to even numbers, which H.264 needs: a 1365×767 window recording becomes 1364×766.
  • Bitrate as in the WebM, capped by size: up to 5 Mbps for 720p, 8 Mbps for 1080p.
  • Measured: a one-minute 1080p VP9 recording of 19.1 MB became an 18.7 MB MP4.

Browsers that can do it

  • Chrome and Edge on Windows, macOS and Android, and Safari, have both encoders.
  • Firefox and Chrome on Linux have no AAC sound encoder, so a WebM with sound can’t become an MP4 there. The page says so as soon as you open the file. A silent recording still works.
  • Phones manage short clips. A long 1080p recording goes faster on a computer.

Where MP4 is needed

  • Sending a screen recording in WhatsApp or iMessage.
  • Saving it to Photos on an iPhone.
  • Putting it into Premiere Pro, iMovie, PowerPoint or a course platform.

When to keep the WebM

For a web page, a WebM is fine: every modern browser plays it, and VP9 often gives a smaller file than H.264 at the same quality. Re-saving also loses a little detail each time, so convert once, from the original recording.

Free, fast and all yours

  • Free forever

    Every tool is free and will stay free. No trial, no ads, no paid plan.

  • No sign-up, no login

    Open the page and start. No account, no email, no password.

  • Instant

    Nothing to upload and no queue: a video opens in a second, a simple trim saves in seconds.

  • No file size limits

    We set none. A file can be as big as your device can handle.

  • No watermarks, no copyright

    No logo on top and no rights claimed: what you make is 100% yours.

  • Made for phones too

    The same tools on iPhone, Android and a computer, with big buttons and plain words.

Questions

Related tools