Cast a Hexagram from a Song
Upload any audio file and cast an I Ching hexagram from its bytes — a deterministic digest, computed and discarded, never stored. Every song has exactly one hexagram.
Give a song its hexagram
The song that carried you through a rough season. The one you looped for a week straight. The one someone sent you once and you've never heard neutrally again. Upload its audio file and it resolves into a hexagram — deterministically: the same file always lands on the same hexagram. Your life's soundtrack has exactly one hexagram that is permanently its own.
How the algorithm works
To be clear, there is no music-analysis mysticism here: we read the audio file's bytes, compute a SHA-256 digest, split the digest's 32 bytes into six bands, and take each band's mean. Bands above the median become yang lines, bands below become yin, stacked bottom to top; the band farthest from the median becomes the single moving line. Every step is written into the result page's computation trace and can be recomputed independently — see the math page.
Privacy: computed, then discarded
The audio file is never stored. Its bytes are read into memory, the digest is computed, and the original is discarded; the casting record keeps only the filename, size, and digest value for verification. The song you upload does not live on our servers.
Why it's worth trying
Traditional casting draws the number of this moment; casting from a song draws the number of the song itself. When a song that carries weight for you resolves into a hexagram, the judgment's ancient imagery collides with your memory of the music — and whatever that collision surfaces is material worth reflecting on. It's the same experience as casting from text through a different door; the photo door is casting from an image.
Reading the result
Same as any cast: the judgment for the situation, then the moving line and the changed hexagram — see changing lines. Afterwards you can generate a share card that shows the full “this song → this hexagram” trail, ready to send to someone who loves the same track.