Enter a price and an amount. The table shows the taker fee on each venue and the win probability you need just to break even. Below 50 cents and above 50 cents the fee works differently on each venue, so compare at the price you actually trade.
| Venue | Fee | Fee % of amount | Break-even win rate | Expected profit |
|---|---|---|---|---|
| Polymarket, sports | $2.00 | 2.0% | 61.2% | - |
| Polymarket, crypto | $2.80 | 2.8% | 61.7% | - |
| Polymarket, politics | $1.60 | 1.6% | 61.0% | - |
| Kalshi | $2.79 | 2.8% | 61.7% | - |
| Binance Prediction | $1.33 | 1.3% | 60.8% | - |
Taker orders only. Kalshi rounds the fee up to the next cent per order, which matters on small orders. Binance Prediction uses its default 2% rate; some topics differ.
Fee = C × rate × p × (1 − p) for C shares at price p, paid by takers only. Rate by category: crypto 0.07; sports, economics, culture, weather and other 0.05; politics, finance, tech and mentions 0.04; geopolitics 0. Source: Polymarket docs.
Fee = M × 0.07 × C × p × (1 − p), rounded up to the next cent. M is a per-series multiplier, 1 on every series we checked. Some series also charge makers 0.0175 × C × p × (1 − p). Sources: Kalshi fee schedule, series fields in the Kalshi API.
Fee = r × min(p, 1 − p) per share, taken out of the shares you receive. r is the topic's fee rate, 2% by default. We matched this to a live Binance quote on 2026-10-14: 1 USDT at 0.74 cost 0.0094960 shares in fees.
A share bought at 60 cents pays $1 if you are right. Without fees you need to be right more than 60% of the time. Fees push that line up. On Polymarket and Kalshi the fee per share peaks at 50 cents, but as a share of the money you spend it is largest on cheap shares: at 10 cents, Polymarket's crypto fee is 6.3% of the amount. On Binance Prediction the fee is a flat 2% of the amount up to 50 cents and shrinks above that.
We tested one popular version of this on Binance Prediction: buying the favourite in 5-minute BTC markets late in the round. Over 152 pre-registered trades it won 88% of the time and still lost 5.1% per dollar, because the prices already sat close to the break-even line. See the ledger.
Not financial advice.
One email when a test finishes: the claim, the rules, the costs, the verdict. Wins and losses. No signals or trade alerts.