The moment-of-decision tool. Enter the price and what you think the true probability is, and get the fee-adjusted expected value, the win rate you need to break even, a Kelly-sized position, and, if you’ve run the Trade Report, a grade against your own track record in this price range. All in your browser, nothing uploaded.
A prediction-market price is a probability. Profit comes from disagreeing with it correctly: paying 60 cents for something you rightly believe is 70% likely earns about 10 cents of expected value per contract, before costs. The two things traders most often skip are the costs, taker fees quietly raise your breakeven several points on mid-priced contracts, and the sizing, where an edge bet too large gets wiped out by an ordinary losing streak before it can pay off.
The checker does that arithmetic in one place, and the history check adds the part no generic calculator can: whether you specifically have made or lost money in this price band and category before. A positive-EV trade in a range where you have historically bled is a signal to slow down, not necessarily to skip, but to demand more edge.
Prefer the pieces individually? See the standalone EV calculator, breakeven win rate, position sizing, and risk of ruin calculators.