GoKawiilOnKey launches as free, open-source Mac app for pitch-matched singing practice
A developer has released OnKey, a free and open-source singing trainer for Apple Silicon Macs. The app listens to songs played through Spotify, Apple Music or YouTube, learns the vocal melody after one playthrough using a vocal-separation model, CREPE pitch tracking and a note model, then displays scrolling notes with the user's pitch overlaid and a line-by-line score on repeat plays. It requires microphone and system audio access, does not store or stream music itself, and uses Shazam and LRCLIB lookups only to identify songs and fetch lyrics.
GoKawiil's interpretation of the reporting above, not reported fact.
The project illustrates how on-device machine learning models, like CREPE for pitch detection and source-separation tools, can now be combined into consumer-grade tools without needing cloud processing or licensed music catalogs. Its privacy approach of keeping audio in memory and avoiding accounts or analytics may appeal to users wary of data collection, though it limits the Mac-only, Apple Silicon audience. As an open-source hobby project shared on Hacker News, its adoption will likely depend on community interest rather than commercial backing.
- OnKey is free, open-source and restricted to Apple Silicon Macs running macOS 14.2 or later.
- It learns a song's melody locally after one play, using vocal separation and the CREPE pitch model, then scores users' singing on later plays.
- It avoids streaming or storing music directly, relying on Shazam and LRCLIB only for song identification and lyrics, with no accounts or analytics.
Blue Yeti USB Microphone — If you're using OnKey to train your singing on a Mac, a quality USB mic like the Blue Yeti will give the app much cleaner pitch data to analyze than your laptop's built-in mic. It's plug-and-play with macOS, so you can start singing along to your favorite tracks with better accuracy right away. Great for practice sessions where precise pitch detection really matters.
See Blue Yeti USB Microphone on Amazon → Affiliate link — we may earn a commission on purchases, at no extra cost to you. Product picked by AI based on this article; it is not a tested recommendation.Source: github.com, 2026-10-22
Published there as: “Show HN: OnKey – I'm a bad singer, so I built an app to show where I'm off-key”
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