Convert WMV to AMR — Free Online Converter
Convert Windows Media Video (.wmv) to Adaptive Multi-Rate Audio (.amr) online for free. Fast, secure video conversion with no watermarks or registration.
Conversion settings — add a file to adjust
Secure Transfer
HTTPS encrypted uploads
Privacy First
Files auto-deleted after processing
No Registration
Start converting instantly
Works Everywhere
Any browser, any device
How to Convert
Upload your .wmv file by dragging it into the upload area or clicking to browse.
Choose your output settings. The default settings work great for most files.
Click Convert and download your .amr file when it's ready.
About WMV to AMR Conversion
WMV files carry WMA audio in Microsoft's ASF container, while AMR (Adaptive Multi-Rate) is a narrowband speech codec developed by ETSI for GSM cellular networks. AMR operates at 8 kHz with bitrates from 4.75 to 12.2 kbps, using algebraic CELP encoding optimized exclusively for human voice. Converting WMV to AMR extracts the audio, downsamples to 8 kHz mono, and encodes it for the most extreme voice compression available — producing files under 6 MB per hour of speech.
Why Convert WMV to AMR?
AMR's sole purpose is ultra-compact voice encoding for mobile telephony. If you have WMV recordings of meetings, depositions, interviews, or phone calls and need the absolute smallest possible audio files for MMS delivery, legacy mobile voice memo systems, or VoIP archival, AMR achieves compression ratios that no other format can match for speech content.
Common Use Cases
- Extracting speech from WMV meeting recordings for MMS distribution to field workers
- Creating ultra-compact voice files from WMV interview recordings for mobile archival
- Converting WMV voicemail recordings to AMR for integration into mobile VoIP systems
- Generating minimal-size audio from WMV conference recordings for feature phone playback
- Preparing WMV deposition audio as AMR files for mobile review by legal teams
How It Works
FFmpeg decodes the WMA audio from the ASF container, downsamples to 8 kHz mono (AMR-NB requirement), and encodes using libopencore_amrnb at the selected bitrate (4.75–12.2 kbps). AMR uses 20ms CELP frames with built-in voice activity detection (VAD) and comfort noise generation (CNG). The output is a raw AMR file or AMR wrapped in a 3GP container for mobile compatibility.
Quality & Performance
At 12.2 kbps, AMR sounds like a clear phone call — perfectly adequate for speech comprehension. Below 7.4 kbps, speech remains intelligible but sounds compressed with noticeable artifacts. Music and non-speech audio are severely distorted at any AMR bitrate — the codec is not designed for them.
Device Compatibility
| Device | WMV | AMR |
|---|---|---|
| Windows PC | Native | Partial |
| macOS | Partial | Partial |
| iPhone/iPad | Partial | Partial |
| Android | Partial | Partial |
| Linux | Partial | Partial |
| Web Browser | No | No |
Recommended Settings by Platform
YouTube
Resolution: 1920x1080
Bitrate: 8-12 Mbps
H.264 recommended for fast processing
Resolution: 1080x1080
Bitrate: 3.5 Mbps
Square or 9:16 for Reels
TikTok
Resolution: 1080x1920
Bitrate: 4 Mbps
9:16 vertical, under 60s ideal
Twitter/X
Resolution: 1280x720
Bitrate: 5 Mbps
Under 140s, 512MB max
Resolution: 960x540
Bitrate: 2 Mbps
16MB limit for standard, 64MB for document
Discord
Resolution: 1280x720
Bitrate: 4 Mbps
8MB free, 50MB Nitro
Tips for Best Results
- 1Always select the highest AMR bitrate (12.2 kbps) unless file size is absolutely critical — the voice clarity improvement is substantial.
- 2Apply a noise reduction filter before conversion to reduce background hiss, which AMR's CELP encoder tends to amplify.
- 3If the WMV contains music or sound effects alongside speech, consider AAC at low bitrate instead — AMR cannot handle non-speech audio.
- 4For better speech quality, investigate AMR-WB (23.85 kbps at 16 kHz) if the receiving device supports it.
Related Conversions
WMV to AMR conversion extracts voice audio into the most space-efficient speech format available. It is specialized for telephony-grade voice delivery, not general audio.
WMV vs AMR
| Feature | WMV | AMR |
|---|---|---|
| Full Name | Windows Media Video | Adaptive Multi-Rate Audio |
| Extension | .wmv | .amr |
| Best For | Windows native | Speech optimized |