We can work with the main audio, video, dictation and recorder formats. Keep the original file wherever possible: repeated conversion can reduce sound quality.
Audio formats
| Extension | Type | Notes |
|---|---|---|
| .aac | Compressed audio | Common on mobile and online platforms |
| .act | Recorder audio | Supported recorder format |
| .aifc | Compressed AIFF | Apple audio variant |
| .aiff | Lossless audio | High-quality Apple/studio format |
| .amr | Compressed speech | Common on phones and voice recorders |
| .ape | Lossless audio | Monkey’s Audio |
| .au | Audio container | Unix/Sun audio |
| .caf | Apple Core Audio | Apple recording and editing format |
| .dct | Dictation audio | Express Dictate/MSRS and similar |
| .ds2 | DSS Pro | Professional digital dictation |
| .dss | Digital dictation | Grundig, Olympus and Philips recorders |
| .dsp truespeech | Speech codec | Legacy compressed speech |
| .dvf | Sony recorder | Sony digital voice format |
| .dvs | Royal recorder | Digital voice recording format |
| .flac | Lossless audio | High quality without lossy compression |
| .ogg | Compressed audio | Open audio container |
| .m4a | Compressed audio | Common on Apple devices and phones |
| .mp2 | Compressed audio | Broadcast/legacy MPEG audio |
| .mp3 | Compressed audio | Widely compatible and easy to transfer |
| .mpc | Compressed audio | Musepack audio |
| .msv | Sony recorder | Sony Memory Stick Voice |
| .qcp | Compressed speech | Qualcomm PureVoice |
| .ra / .rm | RealAudio | Legacy streamed audio |
| .shn | Lossless audio | Shorten audio |
| .spx | Speech codec | Speex audio |
| .voc | Creative audio | Legacy voice/audio format |
| .vox | Telephony audio | Dialogic/voice recording format |
| .wav | Lossless/uncompressed audio | Includes PCM, ADPCM, aLaw, uLaw and GSM 6.10 codecs |
| .wma | Compressed audio | Windows Media Audio |
Video formats
| Extension | Type |
|---|---|
| .3g2 | Mobile video |
| .3gp | Mobile video |
| .asf | Microsoft media container |
| .avi | Video container |
| .divx | Compressed video |
| .dv | Digital video |
| .flv | Flash video |
| .m4v | MPEG-4/Apple video |
| .mkv | Matroska video container |
| .mov | QuickTime video |
| .mp4 | Widely supported audio/video container |
| .mpeg | MPEG video |
| .vob | DVD video object |
| .wmv | Windows Media Video |
Other supported media
We can also assess P3, SRI/VoiceIt, Sanyo recorder files, TheRecordPlayer files used for court or police-station work, and files using PCM, ALaw, ADPCM, CELP, SBC or other embedded codecs. If your extension is not listed, send us the filename and a short non-confidential sample rather than converting it yourself.
Which format should I use?
- Best quality: WAV, AIFF or FLAC retain more detail but create larger files.
- Convenient sharing: MP3 and M4A usually give a practical balance of quality and size.
- Professional dictation: DSS and DS2 are compact and designed for speech.
- Video: MP4 and MOV are widely used; the clarity of the audio track matters more than the container.
Good microphone placement and a quiet room usually make more difference than the extension. See the full company file-format guide or ask us to check a format.