Hi Product Hunt! ChordHelper has experienced large success since its first launch, with 5,000 monthly users on our site. We're launching again since we've changed a lot since our launch. ChordHelper is a web app that allows you to make great chord progressions for your music instantly. Our features include: 🛠️ Build chords on a given key + octave, with guidelines on what chords are in/out of key 🎶 Filter on the root or top note of chords, so you can test different chords for a given note to see which sounds best 🎹 Twelve different chord types, inversions, and beats for customization ⬇️ Download your chord progression as a MIDI file to use in your music All of these features are free and live on the website! We'd love to hear from you what you think :).