WebM to MP3
WebM to MP3 converts the Opus audio in a WebM recording to MP3 in your browser, so the recording never leaves your device.
Drop a video or audio file, paste it, or click to choose one
WebM video or audio, such as a browser recording
Video or audio file · processed on your device, never uploaded
At a glance
- Accepts
- WebM video or audio, plus MKV, MP4 and other common files
- Outputs
- MP3 at 128, 192 or 320 kbps, or 16-bit WAV
- Where it runs
- Entirely in your browser, on your device
- What leaves your device
- Nothing - the file never leaves your device
- Limits
- No lossless copy option, since MP3 players can't play Opus; needs a browser with an Opus decoder (current Chrome, Edge, Firefox and Safari have one)
- Account
- Not required - there is no sign-up
- Price
- Free, with no watermark and no usage cap
- Made by
- Visrut
- Last updated
- 11 October 2026
WebM is what you get from recording inside a browser: a meeting captured with an extension, a voice note from an online recorder, a screen capture from a web app. It plays in browsers but often not in the places you want to send it, like a phone's music app, a podcast editor or an email to someone on an older computer. MP3 fixes that.
How it converts
The browser's own Opus decoder turns the WebM's audio into raw samples, and the LAME encoder writes them out as MP3, both inside a background worker in this tab. Opus is usually recorded at 48 kHz, and the MP3 keeps that rate. In our test, a 10-second WebM with 96 kbps Opus became a 192 kbps MP3 of the same length, give or take 0.05 seconds of encoder padding, in about a quarter of a second.
Choosing a bitrate
- Speech (calls, lectures, voice notes): 128 kbps. A higher MP3 bitrate can't bring back detail the recording never had.
- Music or mixed audio: 192 kbps.
- Editing afterwards: choose WAV instead, so the audio isn't compressed twice before the final export.
Recorded a meeting and need the notes, not the audio? Video to Text transcribes the WebM in your browser.
Frequently asked questions
Where do WebM files come from?
Mostly from browsers. Anything recorded with a web page's record button (an online voice recorder, a browser screen recorder, a video call recording tool) is usually saved as WebM, because that is what Chrome and Firefox record natively. Video downloaded from some websites is WebM too.
Why is there no lossless option for WebM?
The sound in a WebM file is almost always Opus. Opus is an excellent codec, but MP3 players and most audio apps don't accept it, and it can't be placed inside an MP3 or M4A file without re-encoding. So the choices here are MP3, for compatibility, or WAV, for editing.
Will an audio-only WebM work?
Yes. A WebM with no video track, which is what many voice recorders produce, converts exactly the same way. The tool reads whatever audio track is there.
Which browsers can convert WebM to MP3?
Current Chrome, Edge and Firefox, and Safari 26 or later. We tested WebM with Opus audio in Chromium and WebKit, Safari's engine, and both produced correct MP3s.