Sample Opus Files — Download Modern Low-Bitrate Test Audio
Opus (in Ogg container) · .opus · MIME type audio/opus
Download a sample Opus file — the codec that carries WhatsApp and Telegram voice messages, Discord, Zoom and every WebRTC call. Opus beats MP3, AAC and Vorbis at low bitrates and is royalty-free, which is why it has quietly become the most-used audio codec on the planet.
Samples are 64 and 96 kbps in the standard Ogg container (.opus). Chrome, Firefox, Edge and Android play it natively; Safari and iOS support arrived in 2023 but remain inconsistent in some apps, which is worth testing.
Download sample Opus files
| File | Details | Size | Download |
|---|---|---|---|
sample-audio-15s-64kbps.opus | 15 s · OPUS · 96 kbps · 48 kHz · stereo | 182 KB | |
sample-audio-60s-96kbps.opus | 1 min · OPUS · 138 kbps · 48 kHz · stereo | 1.0 MB |
Need one of every audio format? Download the audio sample pack (1.7 MB, one small file of every audio format (9 files)).
Use these files from the command line or CI
Every URL is stable and CORS-open. Pin the SHA-256 in your test and you will know the moment a fixture changes.
# Download one file curl -O https://pnb-website-bucket.s3.us-east-2.amazonaws.com/samples/audio/opus/sample-audio-15s-64kbps.opus # Verify it (SHA-256 is listed for every file above) shasum -a 256 sample-audio-15s-64kbps.opus # Machine-readable index of every sample file curl https://pnb-website-bucket.s3.us-east-2.amazonaws.com/samples/index.json | jq '.files[] | select(.format=="opus")'
Opus format at a glance
| Full name | Opus (in Ogg container) |
|---|---|
| Extensions | .opus |
| MIME type | audio/opus |
| Standard | IETF RFC 6716 (2012) |
| Bitrates | 6–510 kbps; samples at 64 and 96 kbps |
| Internal sample rate | 48 kHz |
| Container | Ogg (also used raw in WebM and WebRTC) |
| Magic bytes | 4F 67 67 53 ("OggS") + OpusHead |
What people test with sample Opus files
- Voice-note upload and playback (messaging apps)
- WebRTC and VoIP tooling
- Safari/iOS playback checks
- Transcoding Opus to MP3/AAC for compatibility
Frequently asked questions
Why do WhatsApp voice notes come as .opus?
Because Opus is tuned for speech at very low bitrates — a minute of voice is well under 500 KB — while still sounding better than MP3 at several times the size. Most apps transcode it to MP3 or AAC when a user exports it.
Are these Opus files safe to download?
Yes. Every file is generated by our own open script from scratch — nothing is scraped or user-uploaded — and contains no scripts, macros or executables. The SHA-256 of each file is published on this page so you can verify what you received.
Can I use the sample Opus files commercially?
Yes. They are free for any purpose, including commercial products, test suites, demos and redistribution, with no attribution required. There is nothing to license and no one to ask.
Can I hotlink these files or use them in CI?
Yes. Every link is a stable direct URL over HTTPS with Access-Control-Allow-Origin: * and long cache headers, so curl, wget, fetch() and test runners can pull them directly. A JSON index of every file is linked from each page (see the command-line section).
Related sample files
Testing a file pipeline? We build them.
Uploads, conversions, previews, document processing and media workflows are the kind of production systems Pine & Birch designs and runs for clients — which is why we needed these files in the first place.
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