I graded 9,800 Kalshi BTC 15-minute windows. The win rate just tracks the price you pay — and flat windows are a coin flip.

I've been logging every signal my model fires on Kalshi's BTC 15-minute markets (KXBTC15M) since March — 9,811 graded so far, win/loss recorded before settlement. Wrote up what the data actually shows, and two things stood out:

1. Near-flat windows are a coin flip. When BTC moves less than 0.02% during the window, the win rate is 50.1% — dead-on chance — and it stays ~50% every single month (50.0 / 52.6 / 48.4 / 50.7 / 46.4%). The median move in those windows is ~$20 on a ~$64k contract, so settlement is basically index-sampling noise, not direction. The model's confidence number is meaningless there.

2. The win rate is just the price. Bucket by entry price and the win rate tracks it almost exactly — 53% at ≤80¢, 99.7% at 100¢. Realized EV is ~zero at every bucket (slightly negative pre-fee). The market's efficient; a high hit rate is bought, not free.

Full write-up with the charts + methodology: https://degenhedge.com/research/kalshi-btc-15-minute-markets/

Raw data if you want to recompute it (filter product=BTC): https://degenhedge.com/results.csv

Curious if others tracking these markets see the same flat-window breakdown.