AMR Won't Open? Convert to SOX Instantly
Fast, instant AMR to SOX conversion. No signup required. Just drop your .amr file and get .sox in seconds.
Batch Settings
音声ファイルの形式変換は、時に思いのほか複雑な作業となりがちです。特にAMR形式は、携帯電話での録音など特定の用途で使われることが多く、汎用性の高いSOX形式への変換は、多くの場面で必要とされます。例えば、大切なビジネスの会話記録を社内プレゼンで共有したい時、あるいは趣味で録りためた朗読音声を友人に聞かせたい時など、異なるデバイスやソフトウェア間での互換性は非常に重要です。当社の変換ツールは、そうした皆様の「もっとスムーズに音声を扱いたい」というご要望に応えるため、直感的で高品質な変換体験を提供いたします。煩雑な設定は不要、数クリックでAMRファイルをSOX形式へ最適化し、皆様のデジタルライフをより豊かなものへと導きます。
- ビジネス会議の議事録共有
- 同人音声作品の配布準備
- 古いガラケー録音のPC保存
日本では、特に古いフィーチャーフォン（ガラケー）で録音されたAMRファイルが未だ多く存在し、これらを最新のPCやスマートフォンで再生・編集するためにSOX形式への変換需要が見られます。
About AMR to SOX Conversion
Dealing with a AMR file that won't open on your device? You're not alone — AMR compatibility issues are one of the most common reasons people search for a file converter. AMR is a speech-optimised audio codec used in mobile voice recordings.
The fix is simple: convert your AMR to SOX. SOX is a widely used file format. This conversion lets you convert between formats quickly, solving the problem in seconds rather than hours of troubleshooting.
Converting AMR to SOX maintains high quality with CocoConvert's optimised encoder settings.
CocoConvert processes your AMR file on secure servers in Germany — upload, convert, download. Your files are encrypted via TLS and automatically deleted within 24 hours. No account needed, no software to install, and it works on any device with a browser.
This conversion is ideal when you When you need a SOX file.
The conversion engine behind CocoConvert uses FFmpeg, Sharp, and qpdf — the same open-source libraries trusted by Netflix, YouTube, and enterprise platforms. Pro users can batch convert up to 100 files at once.
How to Convert AMR to SOX
- 1
Add your AMR file
Drag and drop your .amr file into the converter, or tap "Browse" to pick it from your device. Multiple files are supported for batch processing.
- 2
Pick SOX output
Select .sox as the target format. CocoConvert automatically applies the best quality settings for this conversion.
- 3
Start conversion
Hit the Convert button. The audio engine processes your file server-side — no CPU drain on your device.
- 4
Save your file
Once done, download your .sox file. For batch jobs, download all at once as a zip.
What Happens When You Convert AMR to SOX
Your AMR file is decoded and re-encoded as SOX.
Your AMR file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in SOX format
The converted file is ready for download
Format Comparison
AMR
.amr file
| Extension | .amr |
| MIME Type | audio/amr |
| Category | Audio |
SOX
.sox file
| Extension | .sox |
| MIME Type | audio/x-sox |
| Category | Audio |
Should You Convert AMR to SOX?
When to Convert
- ✓When you need a SOX file
Frequently Asked Questions
Why won't my AMR file open?
AMR files may not open if your device lacks the right codec or application. Converting to SOX — a more widely supported format — usually resolves this. SOX is a widely used file format.
Is it safe to convert AMR to SOX online?
Yes. CocoConvert encrypts your file via TLS, processes it on isolated servers in Germany, and permanently deletes it within 24 hours. Your files are never shared or analysed.
Will I lose quality converting AMR to SOX?
Converting AMR to SOX maintains high quality with CocoConvert's optimised encoder settings. CocoConvert uses high-quality encoder defaults to preserve as much fidelity as possible.
How large can my AMR file be?
Free users can convert files up to 250 MB each. Pro users get a 5 GB limit per file, and Business API users have custom limits.
Can I convert AMR to SOX on my phone?
Absolutely. CocoConvert works in any modern browser — iOS Safari, Android Chrome, and all desktop browsers. No app required.
Versions are pinned in our worker Dockerfile and re-built via CI on every change.