Circle of Fifths

Hi everyone! I’m an indie developer and a music enthusiast. I recently built a little tool called Circle of Fifths — an interactive circle of fifths that helps you understand keys, chords, and modulations in a more intuitive way. When I was learning music theory, I always found static charts too abstract. You can’t hear them, and they don’t really help you feel how keys are connected. So I decided to make one that actually moves — clickable, audible, and visual. Main features: - Click any key to see its key signature, scale, and functional chords. - Hear every chord or scale instantly with real-time playback. - Explore common chord progressions like I-V-vi-IV. - Watch how keys relate and modulate through a rotating visual circle. It’s perfect for: 🎓 music students, 🎹 composers and songwriters, 👩‍🏫 teachers who want a better classroom demo tool. No login, no ads — just open and use. I hope this tool helps more people feel music theory instead of memorizing it. 👉 circle-fifths.com