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Convert AU to AMR
Convert AU to AMR format — 100% browser-based, no upload required.
2 cores · low tier
Drop a file here or click to select
Format will be auto-detected
About these formats
Source
AU
Sun/NeXT AudioSimple audio format from Sun Microsystems. Originally used in Unix systems and Java audio. Typically stores µ-law compressed audio.
Best for
Unix/Java audioLegacy systemsSimple audio storage
Advantages
- + Simple format
- + Java support
- + Compact for telephony
Limitations
- − Outdated
- − Low quality
- − Limited use
Target
AMR
Adaptive Multi-Rate AudioSpeech codec optimized for voice recording. Widely used in mobile phones for voice notes and MMS audio.
Best for
Voice recordingPhone audioMMS messagesLow-bandwidth speech
Advantages
- + Very small files
- + Optimized for speech
- + Mobile standard
Limitations
- − Speech only (poor music)
- − Low quality
- − Limited sample rates