CONVERT AMR → OPUS (AMR to OPUS)
Fast, secure AMR to OPUS conversion. No registration required.
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HOW TO CONVERT AMR → OPUS
Provide the audio file
Drag the AMR onto the uploader. Files up to 25 MB run on the free tier without registration; paid plans go up to 2 GB.
ffmpeg handles the conversion
Our ffmpeg-based pipeline reads sample rate and channel layout, then writes a matching OPUS with ID3 tags intact.
Save the output
Click to download the OPUS. Batch uploads are bundled into a ZIP for single-click retrieval.
Here is the short version — AMR is the narrowband speech codec built for mobile voice recordings and 3G calls. Hence the need for OPUS. A AMR to OPUS conversion is typically about compatibility: some players refuse AMR, many accept OPUS. The audio payload makes the round trip with minimal artefacts when bitrate is left at sensible defaults. Drop a AMR file into the uploader and the OPUS comes back in seconds. Context: AMR is the narrowband speech codec built for mobile voice recordings and 3G calls. Opus is the modern low-latency royalty-free codec used in VoIP, streaming, and WebRTC.
Why convert AMR to OPUS
Moving from AMR to OPUS usually buys compatibility or a friendlier file size. For spoken-word content the difference is inaudible; for high-resolution music pick the highest bitrate the OPUS codec supports to avoid compounding compression.
AMR vs OPUS — Technical specifications
Side-by-side comparison of the technical details.
AMR
- MIME type
- audio/amr
- Extensions
- .amr, .3ga
- Standard
- 3GPP TS 26.071 (narrowband), TS 26.171 (wideband)
- Sample rate
- 8 kHz (AMR-NB); 16 kHz (AMR-WB)
- Bitrates
- 4.75, 5.15, 5.9, 6.7, 7.4, 7.95, 10.2, 12.2 kbps
- MIME Type
- audio/amr
- Extension
- .amr
- Category
- Audio Files
- Full Name
- AMR Audio
- Conversion Engine
- FFMPEG
OPUS
- MIME type
- audio/opus
- Extensions
- .opus, .ogg (container)
- Standard
- RFC 6716 (2012)
- MIME Type
- audio/opus
- Extension
- .opus
- Category
- Audio Files
- Full Name
- Opus Audio
- Conversion Engine
- FFMPEG
- Sample rates
- 8, 12, 16, 24, 48 kHz
- Latency
- 5-60 ms (configurable)
| Specification | AMR | OPUS |
|---|---|---|
| MIME type | audio/amr | audio/opus |
| Extensions | .amr, .3ga | .opus, .ogg (container) |
| Standard | 3GPP TS 26.071 (narrowband), TS 26.171 (wideband) | RFC 6716 (2012) |
| Sample rate | 8 kHz (AMR-NB); 16 kHz (AMR-WB) | — |
| Bitrates | 4.75, 5.15, 5.9, 6.7, 7.4, 7.95, 10.2, 12.2 kbps | — |
| MIME Type | audio/amr | audio/opus |
| Extension | .amr | .opus |
| Category | Audio Files | Audio Files |
| Full Name | AMR Audio | Opus Audio |
| Conversion Engine | FFMPEG | FFMPEG |
| Sample rates | — | 8, 12, 16, 24, 48 kHz |
| Latency | — | 5-60 ms (configurable) |
AMR vs OPUS — Strengths and limitations
What each format does best, and where it falls short.
AMR Strengths
- Extremely low bitrate — 4.75-12.2 kbps for speech.
- Designed for error-prone mobile channels — handles packet loss gracefully.
- Tiny file sizes — hours of voice in a few MB.
- Mandatory codec in all 3G/UMTS phones — universal cellular compatibility.
Limitations
- Speech-only — music sounds distorted.
- Narrowband (8 kHz sample rate) — muffled compared to modern codecs.
- Patent-encumbered until recently — licensing fees slowed adoption outside telephony.
OPUS Strengths
- Best-in-class quality across the entire bitrate range.
- Royalty-free and patent-free.
- Ultra-low latency — suitable for live voice and music.
- Handles speech and music equally well — no need to switch codecs.
- Mandatory codec in WebRTC, so supported in every browser by design.
Limitations
- Very low hardware decoder adoption — software-only on most phones.
- Older platforms (legacy Windows apps, old cars) may not play .opus files.
- Container semantics confusing — Opus lives inside Ogg, WebM, or MP4.
Quality & Compatibility
Sample rate, channel layout and bit depth are preserved by default: a 44.1 kHz stereo AMR becomes a 44.1 kHz stereo OPUS. Metadata — title, artist, album, cover art — travels where both formats support it. Protected DRM content cannot be converted legally and is rejected.
Tips for Best Results
- Check the podcast host specification before choosing bitrate — some mandate CBR 64 kbps, others accept VBR up to 192 kbps.
- Preserve ID3 tags by editing them before conversion; Mp3tag and MusicBrainz Picard handle round-tripping cleanly.
- If the AMR is 24-bit studio audio, the OPUS at 16-bit is sufficient for listening; higher is wasted on consumer playback gear.
Frequently Asked Questions
Lossy-to-lossy conversions (most combinations) re-compress the audio, which technically introduces some loss. At a 192 kbps or higher target it is inaudible on normal equipment. Lossy-to-lossless conversions freeze the existing quality but cannot improve it; lossless-to-lossy transcodes are only as good as the target bitrate you choose.
For voice content (podcasts, audiobooks, lectures) 128 kbps is indistinguishable from higher bitrates. For music, 192-256 kbps covers most listening; 320 kbps is the ceiling for OPUS and the right choice for audio you plan to edit further. Above that, prefer a lossless target instead.
Yes. Title, artist, album, year and cover art travel from the AMR container to the OPUS container automatically where both formats support them. If a tag field has no OPUS equivalent, it is dropped silently. Use any tag editor (Mp3tag, MusicBrainz Picard) to fine-tune afterwards.
AMR Audio
Source formatAMR (Adaptive Multi-Rate) is an audio format optimized for speech, used in phone calls.
Opus Audio
Target formatOpus is a versatile, open-source audio codec optimized for both speech and music at very low bitrates. It is the standard for WebRTC voice calls and excels at real-time communication.
Going the other way? Convert OPUS back to AMR with the same engine.
Common Use Cases
Share across platforms
Send OPUS files to anyone without worrying about whether they have the right software for AMR.
Embed in documents
Drop OPUS output into Word, Google Docs, PowerPoint, Notion or a website without conversion warnings.
Optimize size
OPUS often produces smaller files than AMR for web, email and storage.
Archive & future-proof
Store in a widely-supported format that will still open on future operating systems without legacy plugins.
AMR vs OPUS — Typical file sizes
Approximate file sizes for common scenarios.
- 1-min voice memo 45-90 KB
- 1-hour voicemail archive 3-5 MB
- Voice call (24 kbps) 180 KB/min
- Podcast (48 kbps) 21 MB/hour
- Music (128 kbps) ~1 MB/min
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Related comparisons
See these formats side by side to understand which fits your use case best.
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