NCM is decrypted locally, then converted to M4A (AAC) for smooth playback on iPhone and iTunes. The whole decrypt-and-convert run stays in your browser.
About NCM
NetEase Cloud Music encrypted format
NCM is the encrypted cache format used by NetEase Cloud Music and cannot be played directly. This tool decrypts it in your browser and restores it to MP3 or FLAC.
- Auto-decrypts to common formats
- Encrypted, must be decrypted first
About M4A
Common audio container in Apple ecosystem
M4A is an MPEG-4 audio container, usually AAC or ALAC encoded, widely used across Apple devices and iTunes with a good balance of size and quality.
- Good balance of size and quality
- Native to the Apple ecosystem
- Limited support on some non-Apple players
NCM to M4A FAQ
Will converting NCM to M4A lose quality?
Both NCM and M4A are lossy formats. Re-compression may further reduce quality — choose a higher bitrate to minimize additional loss.
Will the file size change after conversion?
Converting to a lossless format (WAV) usually increases size, while converting to a lossy format (MP3, AAC) usually decreases it, depending on the chosen bitrate and sample rate.
How do I batch convert NCM to M4A?
Just drop multiple NCM files in; they are converted to M4A one by one via a queue. You can download them individually or as a single ZIP.