Step 1: Provide your Opus files using the button above or by toss and let go.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Fetch your converted AMR files.
Opus to AMR Conversion FAQ
What bitrate does the AMR file end up at?
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A lossy AMR is encoded at 192 kbps by default. The Audio Quality setting also offers 320 kbps for the best quality and 128 kbps for a smaller file. A lossless AMR (WAV, FLAC) ignores the bitrate and keeps every sample.
Is converting Opus to AMR a second round of lossy compression?
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Yes, and it is worth planning around. Both formats are lossy, so the AMR encoder is working from audio that has already been through one psychoacoustic pass, and its own decisions compound the first set. At 192 kbps or above the result is still transparent for most listening. If you have a lossless master anywhere, encoding the AMR from that instead avoids the double pass entirely. Opus scales from 6 kbps mono speech to 510 kbps stereo music in the same bitstream and switches modes automatically. AMR is a narrowband speech codec running between 4.75 and 12.2 kbps, modelling the human vocal tract rather than the full audio spectrum.
Will my track titles and album art survive the Opus to AMR conversion?
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Not intact. Opus carries a proper metadata block, but AMR has no standard place for artist, album, track number or cover art, so tags are dropped rather than mangled. Keep the Opus as the tagged copy, or re-tag afterwards with a tool like Mp3tag or MusicBrainz Picard. AMR destroys music: its 8 kHz bandwidth removes everything above telephone frequencies, and no amount of re-encoding brings it back.
Why does music sound so poor in this conversion?
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Because one side of it is a speech codec rather than a music codec. It models the human vocal tract and discards everything outside telephone bandwidth, which is fine for a voice memo and destructive for anything with instruments in it. Converting away from it cannot restore the missing frequencies — they were never encoded in the first place. Opus is almost never supported by standalone hardware — assume software playback only, and expect car stereos to ignore it.
Will going from Opus to AMR actually reduce my audio quality?
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If Opus is lossy (MP3, AAC) and AMR is lossless (WAV, FLAC), the AMR is no better than the Opus — you cannot recover information already discarded by the lossy Opus codec. If Opus is lossless and AMR is lossy, expect the AMR encoder to recompress; at 192 kbps the loss is imperceptible to most ears.
Can I batch-convert hundreds of Opus files into AMR?
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Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
Can I normalize loudness in the Opus to AMR step?
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Not in this step. The converter has no loudness setting and leaves the level as it is. To even out the volume, run the finished AMR through a Normalize tool on this site.
Will the AMR play on my car stereo / iPod / Sonos / Bluetooth speaker?
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MP3 plays almost everywhere. AAC plays on Apple devices, most Android phones and Sonos. FLAC plays on Sonos and Android but not on older iPods, and WAV plays on nearly everything but makes large files. There are no device presets on this page, so choose the target format your player supports. AMR makes voice recordings absurdly small — an hour of speech fits in a few megabytes — and it is what many phones still record calls in.
Is my Opus file private during conversion?
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Yes. Uploaded Opus files are processed on our own conversion servers, no person reviews them, and they are never shared. The upload and the converted AMR are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.
