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Convert AU to MP4
Convert AU to MP4 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- − Outdated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
MP4
MPEG-4 Part 14The most widely used video container. Supports H.264/H.265 video with AAC audio, offering excellent compatibility across all devices and platforms.
Best for
Web videoStreamingSocial mediaMobile video
Advantages
- + Universal compatibility
- + Good compression
- + Streaming support
- + Hardware accelerated
Limitations
- − Proprietary codecs (licensing)
- − Not ideal for editing