How to Spot Mispricings on Polymarket Crypto Markets
Most Polymarket crypto markets — "Will Bitcoin hit $X by date?", "Will ETH be above $Y?" — are priced by the crowd. The crowd is often right, but not always. The edge is finding the markets where the crowd's price disagrees with a sharper reference, and the sharpest reference in crypto is the options market.
Why Deribit is the reference
Deribit is where professionals hedge billions of dollars of crypto risk. Its options prices encode a continuous, arbitrage-tight view of the probability that BTC or ETH ends above any given strike by any given date. You can convert that options surface into a fair probability for almost any Polymarket crypto question:
- "Above $X by date" → a European digital, fair value = N(d2) from the implied volatility at that strike and expiry.
- "Hit/reach $X by date" → a one-touch barrier, priced with a reflection model.
The gap is the signal
Once you have the options-implied fair probability, compare it to Polymarket's price. A wide gap means the retail order book disagrees with where pros are hedging — and the options market is usually the one that's right. A positive gap (Polymarket price > fair) means the market is overpricing the outcome; a negative gap means it's underpricing it.
The honest caveats
This isn't free money. Fair values are model estimates and can be wrong; markets can stay mispriced longer than you can stay solvent; and after fees a small gap isn't worth trading. Most Polymarket crypto markets are reasonably efficient — you'll often find only one or two real gaps at a time. The point is to measure the gap consistently rather than guess.
That's exactly what PolyGap's terminal does: it prices every live Polymarket crypto market against Deribit's options curve and surfaces the gaps, refreshed every 10 minutes. You can also pull the same data into your own code via the REST API.