WebM to OPUS Converter

How to Convert WebM to Opus Online

1. Upload Your WebM File: Drag and drop or click "+ Add Files" to select one or more .webm videos. Batch is supported — queue dozens at once.
2. Pick Quality Preset and Bitrate: Defaults to Highest, which targets 128 kbps stereo. Drop to Medium (96 kbps) for podcasts or Low (64 kbps) for voice memos. For full control, switch from Quality Preset to Custom Bitrate (Constant or Variable, 6–510 kbps).
3. Set Audio Channel, Sample Rate, and Trim (Optional): Leave Audio Channel and Audio Sample Rate at Original to keep the source track's layout, or force Mono / 48000 Hz to shrink size. Use Trim to clip a start time and duration in HH:MM:SS.ms.
4. Convert and Download: Click Convert. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark, never shared.

Why Convert WebM to Opus?

WebM is a container, not a codec. A .webm file from YouTube, OBS, Chrome's MediaRecorder API, or a Discord screen capture usually carries VP8/VP9 video plus an Opus or Vorbis audio track. Extracting that audio to a standalone .opus file is the cleanest way to keep just the sound — for a podcast clip, a voice memo, a music sample, or a transcription pipeline — at the smallest size today's codecs can deliver.

• Strip video from a screen recording — A 10-minute OBS or Loom capture saved as WebM can be hundreds of MB. Pulling out the Opus audio leaves a file roughly 5–15 MB depending on bitrate, perfect for sharing the audio of a meeting or lecture.
• Feed speech-to-text pipelines — Opus is the on-the-wire format for Whisper.cpp, Deepgram, and Google Speech-to-Text. Converting upstream avoids a server-side re-encode and preserves the low-frequency detail those models train on.
• Replace MP3 in modern apps — Opus delivers transparent quality at roughly half the bitrate of MP3 at the same perceived quality. A 96 kbps Opus file sounds like a 160 kbps MP3 and is supported natively by Discord, WhatsApp (since 2016), Telegram, Chrome, Firefox, Edge, and Safari 11+ on iOS and macOS High Sierra (September 2017).
• Voice memos and podcasts under 64 kbps — Opus's SILK layer is tuned for speech and stays intelligible down to 6 kbps narrowband. A 60-minute interview at 32 kbps mono lands around 14 MB.
• Royalty-free distribution — Opus is IETF standard RFC 6716 (Sept 10, 2012), and Xiph.Org's reference implementation is BSD-licensed. No patent royalties or licensing fees apply, unlike MP3's expired-but-still-debated patent history.

WebM (Opus) vs Opus Container — What Actually Changes

Opus Bitrate Quick Guide

Frequently Asked Questions

My WebM already has an Opus track — does this re-encode it?

Yes — this converter always re-encodes; it doesn't do a raw stream copy. Even with the Highest preset and Audio Channel / Sample Rate at Original, the Opus track is decoded and re-encoded into the Ogg container. At a matched bitrate the generational loss is negligible (Opus-to-Opus is very forgiving), but it isn't a byte-for-byte copy. For a genuine passthrough, a desktop tool like ffmpeg (-c:a copy) is the option.

How do I know whether my WebM has Opus or Vorbis audio?

Open the file in VLC and check Tools → Codec Information, or run ffprobe file.webm from the command line. YouTube downloads since late 2014, Chrome's MediaRecorder API, OBS WebM output, and Discord screen recordings all use Opus by default. Older WebM files (pre-2013) and some legacy YouTube uploads still use Vorbis — those will always require a re-encode here.

Why does Opus sound better than MP3 at the same bitrate?

Opus is a hybrid codec that switches between two engines: SILK (from Skype, tuned for speech) and CELT (from Xiph, tuned for music), often blending them per frame. It was designed in 2010–2012 with 20+ years of psychoacoustic research baked in, while MP3 dates to 1993. Independent listening tests (Hydrogenaudio, Xiph) consistently show Opus at 64 kbps matching MP3 at 128 kbps, and Opus at 96 kbps matching MP3 at 160–192 kbps.

Does iPhone and Mac play .opus files?

Native Opus support landed in iOS 11 and macOS High Sierra (Sept 2017). Files Live Player, VLC for iOS, and the Files app all play .opus directly. On older iOS, install VLC. Note: AirDrop and the macOS Finder Quick Look preview work; iTunes / Apple Music library import does not — convert to AAC for the iTunes library.

What's the largest WebM I can convert here?

There's no hard cap that you'll hit for typical use — multi-GB files are fine because processing runs on our servers tab against our edge nodes, not a single small server slice. For multi-hour 4K screen recordings, expect the upload to be the slow part; the conversion itself is quick because pulling the Opus audio out of a WebM and re-encoding it is far lighter than a video transcode.

Should I pick Constant Bitrate (CBR) or Variable Bitrate (VBR)?

VBR is the right default and what the reference opusenc uses unless you override it. It allocates more bits to complex passages (music, multiple voices) and fewer to silence, giving better quality per byte. Pick CBR only when the downstream expects a predictable rate — some streaming endpoints, hardware decoders, or fixed-bandwidth voice channels.

Can I convert just a clip — say minute 12 to minute 15?

Yes. In Advanced Options expand Trim, enter start 00:12:00.000 and duration 00:03:00.000 in the HH:MM:SS.ms boxes. The output is a 3-minute .opus cut. Keeping all other settings at Original applies just the trim and re-encodes at the source's quality target, so the added loss is negligible.

Why Opus instead of WAV for a transcription pipeline?

Whisper, Deepgram, Google Speech-to-Text, and Azure Speech all accept Opus natively and internally resample to 16 kHz mono anyway. A 1-hour interview is roughly 600 MB as 48 kHz/16-bit WAV but only 14 MB as 32 kbps Opus mono — same recognition accuracy, 40× smaller upload. For long-form, convert WebM to MP3 only if your tool predates 2018 and lacks Opus support.

What's the difference between this page and "Extract Audio from WebM"?

This page targets the Opus container specifically. If you need MP3 instead (for older car stereos, iTunes import, or legacy tools), use WebM to MP3. For lossless WAV (audio editing, mastering), use WebM to WAV. For AAC inside an M4A (Apple ecosystem), use WebM to M4A.