Kalshi Fee & Prediction Market Payout Calculator
Calculate Kalshi fees and payouts, then compare net profit across prediction markets.
Results
| Platform | Fees | Net Profit | ROI |
|---|---|---|---|
| Kalshi (Taker) | $1.751 | $48.25 | 96.5% |
| Kalshi (Maker) | $0.438 | $49.56 | 99.1% |
| PredictIt | $5.000 | $45.00 | 90.0% |
| Polymarket | $1.000 | $49.00 | 98.0% |
| Polymarket US | $1.500 | $48.50 | 97.0% |
| Novig (Pregame) | $0.000(no fee) | $50.00 | 100.0% |
| Novig (Live) | $0.750 | $49.25 | 98.5% |
| Opinion | $25.000(min fee) | $25.00 | 50.0% |
| Predict.fun | $25.000(min fee) | $25.00 | 50.0% |
| ProphetX | $1.000(on profits) | $49.00 | 98.0% |
Polymarket fees vary by market category. Opinion has a $0.25 minimum fee per contract and requires a minimum $5 purchase. ProphetX charges 2% on profits only (no fee on losing trades). All fees shown are taker fees. Kalshi and Polymarket use a P×(1-P) curve; fees are highest at 50¢ and approach zero near extremes.
What does this calculator do?
This tool estimates the per-contract trading fees you should expect to pay on popular prediction markets and displays them side by side so you can make apples-to-apples comparisons. Prices on exchanges are quoted in dollars per $1 payoff — for example, 0.60 means you pay sixty cents now and receive $1 if the event resolves in your favor. Each platform layers on fees differently, and because those policies affect your true cost in different ways, a simple price comparison can be misleading.
Kalshi charges a transaction fee when you place orders — taker fees are higher than maker fees, and both scale with contract price. PredictIt charges a fee only when you win: 10% of net profit, which sounds modest but compounds significantly on winning positions. Polymarket uses category-specific fee curves, with some categories exempt. The calculator normalizes these schedules so you can compare total fees, winning net profit, and ROI at the same entry price and contract count.
Use this as a Kalshi payout calculator by entering the contract price and quantity: the results show the winning profit after taker or maker fees and the resulting ROI. If you're sizing a single directional bet, add the relevant fee to your entry price to understand your effective cost basis. If you are comparing two platforms, compare price + fee across venues rather than raw price alone. If you are building a cross-exchange hedge, remember that Kalshi's fee is paid at entry regardless of outcome, while PredictIt's fee reduces proceeds only in the scenario where that leg wins. Many edges look healthy in a spreadsheet but shrink after you incorporate platform specifics — this page helps you sanity-check that effect quickly before you commit capital.
We don't include account-level or withdrawal fees (e.g., PredictIt's 5% cash-out charge) because those depend on personal behavior. We also assume orders are filled at your stated price with sufficient liquidity. Slippage, partial fills, or cancellations can change your economics more than the fee itself. Use this alongside the Expected Value and No-Vig calculators when you want a fuller picture of whether a quote is truly attractive after frictions. For how these fee structures play out against liquidity, funding, and market selection, see our Polymarket vs Kalshi comparison.