Add your AMR file
Drop one or more .amr files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
AMR to OPUS
Re-encoding .amr audio as .opus changes how the sound is compressed and which players will accept it. Free, private, and validated — the file never leaves your browser.
100% private for supported formats
Runs on your deviceConvert supported files
Drop AMR files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting Adaptive Multi-Rate audio to Opus audio
Re-encoding .amr audio as .opus changes how the sound is compressed and which players will accept it. An .amr file stores speech compressed with the Adaptive Multi-Rate codec, engineered to squeeze a voice call into a few kilobits per second. Feature phones saved voice notes and MMS clips as .amr, and the format still surfaces in old phone backups and some Android recorder apps.
An .opus file contains audio compressed with the Opus codec, stored in an Ogg container. Opus represents the current state of the art in lossy audio, beating MP3, AAC, and Vorbis in listening tests at nearly every bitrate from whisper-thin speech settings up to transparent music encoding. For this route the practical draw is best-in-class efficiency at essentially every bitrate and royalty-free with an open reference implementation — balanced against older car stereos, AV receivers, and MP3 players have never heard of it, which is worth knowing before you commit a large batch.
Why convert AMR to OPUS?
The practical trigger for this conversion is usually a mismatch: with .amr, telephone-grade fidelity: nothing above roughly 3.4 kHz survives. Switching to .opus buys you best-in-class efficiency at essentially every bitrate, which is why it is the better fit for compressing podcast and voice-chat audio to tiny files. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
AMR vs OPUS at a glance
| Aspect | Adaptive Multi-Rate audio (.amr) | Opus audio (.opus) |
|---|---|---|
| Format type | Lossy — discards detail it judges invisible to shrink files | Lossy — discards detail it judges invisible to shrink files |
| How it stores data | narrowband AMR samples at 8 kHz, mono only, across bitrates from 4.75 to 12.2 kbps | the hybrid SILK/CELT design switches coding modes automatically based on content |
| Strongest at | retrieving voicemail exports and call recordings from old handsets | compressing podcast and voice-chat audio to tiny files |
| Weak spot | telephone-grade fidelity: nothing above roughly 3.4 kHz survives | older car stereos, AV receivers, and MP3 players have never heard of it |
| Metadata | none; the storage format is a bare magic number followed by speech frames, with no tagging structure at all | vorbis comments in the OpusTags header, including cover art via METADATA_BLOCK_PICTURE, plus an output-gain field used for loudness normalization |
Pick OPUS as the output
Select .opus in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if OPUS is selectable, the route is real and validated.
Convert on your device
Press Convert. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid OPUS file. Outputs keep the original filename with the .opus extension.
AMR to OPUS questions, answered
Will converting AMR to OPUS lose quality?
A second lossy step always costs a little, because amr is lossy-oriented and opus is lossy-oriented and each encoder discards detail differently (generation loss). At the default quality the difference is rarely visible; avoid repeated round-trips between .amr and .opus.
Is it private to convert AMR files here?
Yes — the .amr file is processed inside your browser tab and never uploaded. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device. Close the tab and the file is gone from memory.
Where will the OPUS file work?
Chrome, Firefox, and Edge have played Opus for a decade and Android supports it natively, while Safari initially accepted the codec only inside CAF or WebM wrappers before extending support to .opus files. Legacy hardware such as older car head units remains the real gap, and conversion to MP3 or AAC bridges it.
Will the OPUS file be bigger or smaller than my AMR?
It depends on the content: the hybrid SILK/CELT design switches coding modes automatically based on content. Convert one representative file first and compare before batch-processing a large set.
What happens to the metadata in my AMR file?
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, none; the storage format is a bare magic number followed by speech frames, with no tagging structure at all; none of it is transmitted anywhere because the file never leaves your browser.