# Prediction market fee calculator > Enter a contract price and size to compare the fees on Kalshi, Polymarket US, OG, Robinhood and ForecastEx, with your total cost, break-even chance and odds after fees. - URL: https://safebet.ai/us/prediction-markets/fee-calculator/ - Markdown version: https://safebet.ai/us/prediction-markets/fee-calculator/index.html.md - Last updated: 2026-10-19 - Publisher: SafeBet.ai - Editorial policy and advertiser disclosure: https://safebet.ai/editorial-policy/ USA · Prediction markets · Free tool See what a trade really costs on Kalshi, Polymarket US, OG, Robinhood and ForecastEx: the fee, your break-even chance and the odds you actually get. By [SafeBet.ai Research Team](https://safebet.ai/editorial-policy/) Updated October 19, 2026 [8 sources](https://safebet.ai/us/prediction-markets/fee-calculator/#sources) ## How the calculator works Pick a platform, enter the price of the contract in cents and how many contracts you’re buying, and say whether your order fills immediately (taker) or waits in the order book as a limit order (maker). The calculator applies that platform’s published fee schedule and shows what leaves your account, what you get back if you’re right, and the probability you need to be right just to break even. The table repeats the same order on the other four platforms in our [ranking of the best US prediction markets](https://safebet.ai/us/prediction-markets/). Three of the five charge in proportion to **price × (1 − price)**, so a 50¢ contract costs the most to trade and a 5¢ or 95¢ contract almost nothing. Robinhood adds a capped commission to the exchange fee, and Interactive Brokers charges a flat cent on ForecastEx. The full schedules, with deposit and withdrawal fees, are in our [prediction market fees guide](https://safebet.ai/us/prediction-markets/prediction-market-fees/). ## The fee schedules used | Platform | Taker | Maker | | -------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------- | | [Kalshi](https://safebet.ai/us/prediction-markets/kalshi-review/) Kalshi exchange | 0.07 × contracts × price × (1 − price), rounded up to the next cent (at most 1.75¢ per contract) | Free on most markets | | [Polymarket US](https://safebet.ai/us/prediction-markets/polymarket-review/) Polymarket US exchange | 0.0695 × contracts × price × (1 − price), rounded to the nearest cent (at most 1.74¢ per contract) | Rebate of 0.0125 × contracts × price × (1 − price), up to 0.31¢ per contract | | [OG (Crypto.com)](https://safebet.ai/us/prediction-markets/crypto-com-review/) Crypto.com's exchange (NADEX) | 0.07 × contracts × price × (1 − price) (at most 1.75¢ per contract), charged when you open and when you close | 0.0175 × contracts × price × (1 − price), up to 0.44¢ per contract | | [Robinhood](https://safebet.ai/us/prediction-markets/robinhood-review/) Kalshi-listed contract through Robinhood | Commission of 10% × price × (1 − price) per contract (5% with Gold), capped at 1¢, plus a 1¢ exchange fee per contract | Same as taker | | [Interactive Brokers (ForecastEx)](https://safebet.ai/us/prediction-markets/interactive-brokers-review/) ForecastEx through IBKR | No commission; flat 1¢ exchange fee per contract on each side of a trade | Same as taker | ## What 100 contracts cost The fee on 100 contracts at three prices, as a taker and as a maker, calculated from the schedules above (Robinhood without Gold). | Platform | Taker | | | Maker | | | | -------------------------------- | ----- | ----- | ----- | ------------ | ------------ | ------------ | | | 20¢ | 50¢ | 90¢ | 20¢ | 50¢ | 90¢ | | Kalshi | $1.12 | $1.75 | $0.63 | $0.00 | $0.00 | $0.00 | | Polymarket US | $1.11 | $1.74 | $0.63 | $0.20 rebate | $0.31 rebate | $0.11 rebate | | OG (Crypto.com) | $1.12 | $1.75 | $0.63 | $0.28 | $0.44 | $0.16 | | Robinhood | $2.00 | $2.00 | $1.90 | $2.00 | $2.00 | $1.90 | | Interactive Brokers (ForecastEx) | $1.00 | $1.00 | $1.00 | $1.00 | $1.00 | $1.00 | To turn a price into sportsbook-style odds, or to check whether a price is good value against your own estimate, see [how to read prediction market prices as odds](https://safebet.ai/us/prediction-markets/prediction-market-odds/) and our [EV calculator](https://safebet.ai/tools/ev-calculator/). [**Compare the 5 best prediction markets in the USA** Ranked on regulation, fees, features and payouts · Kalshi, Robinhood, Crypto.com (OG) and more See the ranking](https://safebet.ai/us/prediction-markets/) ## Frequently asked questions ### How are prediction market fees calculated? Kalshi, Polymarket US and OG charge a fee per contract in proportion to price × (1 − price), which peaks at a 50¢ price: about 1.75¢ per contract on Kalshi and OG and 1.74¢ on Polymarket US. Robinhood adds a commission of up to 1¢ per contract to a 1¢ exchange fee, and Interactive Brokers charges a flat 1¢ per contract on ForecastEx with no commission. Our [fees guide](https://safebet.ai/us/prediction-markets/prediction-market-fees/) has every schedule. ### What is the difference between a taker and a maker? A taker fills an order that is already in the order book and pays the standard fee. A maker places a limit order that waits to be filled: most maker orders are free on Kalshi, earn a rebate on Polymarket US, and pay a quarter of the taker fee on OG. Robinhood and ForecastEx charge both the same. ### What does “break-even chance” mean? The probability you need to be right for the trade to break even after fees: your total cost divided by the $1-per-contract payout. Buying 100 contracts at 50¢ for $51.75 all-in on Kalshi needs the event to happen more than 51.75% of the time, which is the same as betting at about -107. ### Does the calculator include deposit and withdrawal fees? No, only trading fees. Bank transfers are free almost everywhere, but card and PayPal deposits, instant withdrawals and extra withdrawals can cost more than the trading fee; the [fees guide](https://safebet.ai/us/prediction-markets/prediction-market-fees/) lists them per platform. ### Why do the odds after fees differ from the price? Because the fee raises what you pay per contract. A 40¢ contract plus Kalshi’s 1.68¢ taker fee costs 41.68¢, which converts to about +140 rather than the +150 the bare price implies. The bid-ask spread in thin markets adds a further cost the calculator can’t see. ## Keep reading [Guide · 6 min **Prediction market fees compared** Most US prediction markets charge a trading fee per contract that peaks when the price is 50¢: about $1.75 per 100 contracts on Kalshi and OG, $1.74 on Polymarket US, $2.00 through Robinhood and $1.00 on Interactive Brokers' ForecastEx. Deposit and withdrawal fees can matter just as much, so compare the total cost for the way you'll fund your account. Read](https://safebet.ai/us/prediction-markets/prediction-market-fees/) [Guide · 4 min **How to read prediction market prices as odds** A prediction market price in cents is the market's implied probability: a contract at 40¢ means roughly a 40% chance. To get decimal odds, divide 1 by the price (1 ÷ 0.40 = 2.50); in American odds a 40¢ price is +150 and a 60¢ price is -150. Trading fees and the bid-ask spread make the odds you actually get slightly worse. Read](https://safebet.ai/us/prediction-markets/prediction-market-odds/) [Guide · 5 min **Prediction markets vs sportsbooks** A sportsbook sets the odds and takes the other side of your bet; a prediction market is an exchange where you trade contracts with other people and pay a fee. Prediction markets often have lower costs on popular markets and let you sell early, but sportsbooks are licensed by your state, while sports event contracts are still legally contested in many states. Read](https://safebet.ai/us/prediction-markets/prediction-markets-vs-sportsbooks/) ## Sources We verify facts against primary sources (regulators, court records, operators’ own terms) wherever possible. 1. [Fees](https://help.kalshi.com/en/articles/13823805-fees) — Kalshi , accessed 2026-09-30 2. [Kalshi Fees Explained (quoting the fee schedule effective 2026-07-07)](https://polykal.net/kalshi-fees-explained/) — polykal.net , 2026-09-28 3. [Polymarket US fees (schedule effective 2026-09-25)](https://docs.polymarket.us/fees) — Polymarket US , accessed 2026-09-30 4. [Fees & Limits](https://help.og.com/en/articles/12958828-fees-limits) — OG.com , accessed 2026-09-30 5. [Robinhood Derivatives Standard Pricing Fee Schedule](https://cdn.robinhood.com/assets/robinhood/legal/RHD_Fee_Schedule.pdf) — Robinhood Derivatives, LLC , 2026-05-28 6. [Event contracts overview](https://robinhood.com/us/en/support/articles/event-contracts-overview/) — Robinhood , accessed 2026-09-30 7. [IBKR Prediction Markets commissions](https://www.interactivebrokers.com/en/pricing/commissions-events.php) — Interactive Brokers , accessed 2026-09-30 8. [ForecastEx regulatory information and fee schedule](https://forecastex.com/regulatory) — ForecastEx , accessed 2026-09-30 Researched and written by [SafeBet.ai Research Team](https://safebet.ai/editorial-policy/) · Betting analysts & data scientists The team behind SafeBet.ai’s AI sports picks: data analysts, AI engineers and sports bettors based in Maastricht. Since 2021 our models have analyzed 30,088 matches. We review betting, casino and prediction-market platforms against a published methodology and cite official sources for every fact. [Editorial policy](https://safebet.ai/editorial-policy/) [How we rank](https://safebet.ai/us/prediction-markets/how-we-rank/) [About SafeBet.ai](https://safebet.ai/about/) [Report an error](https://safebet.ai/support/) 18+ Prediction markets require you to be 18+ (some platforms 21+) and availability varies by state. Only play with money you can afford to lose. Gambling problem? Call or text [1-800-MY-RESET](tel:+18006973738) (National Problem Gambling Helpline, 24/7) or read our [responsible gambling guide](https://safebet.ai/responsible-gambling/). Top 5 prediction markets · USA 1. [1 **Kalshi** Best overall 9.6](https://safebet.ai/us/prediction-markets/kalshi-review/) 2. [2 **Robinhood** Best for investors 9.0](https://safebet.ai/us/prediction-markets/robinhood-review/) 3. [3 **Crypto.com (OG)** Best for flexible deposits 8.6](https://safebet.ai/us/prediction-markets/crypto-com-review/) 4. [4 **Polymarket** Best for low fees 8.5](https://safebet.ai/us/prediction-markets/polymarket-review/) 5. [5 **Interactive Brokers** Best for earning interest 8.1](https://safebet.ai/us/prediction-markets/interactive-brokers-review/) [Full ranking](https://safebet.ai/us/prediction-markets/) Free prediction market tools - [Prediction market legit check](https://safebet.ai/us/prediction-markets/legit-check/) - [Prediction market fee calculator](https://safebet.ai/us/prediction-markets/fee-calculator/) Prediction markets guides - [How prediction markets work](https://safebet.ai/us/prediction-markets/how-prediction-markets-work/) - [How to check a platform is legit](https://safebet.ai/us/prediction-markets/safe-prediction-markets/) - [Are prediction markets legal?](https://safebet.ai/us/prediction-markets/are-prediction-markets-legal/) - [Prediction markets vs sportsbooks](https://safebet.ai/us/prediction-markets/prediction-markets-vs-sportsbooks/) - [Prediction market fees compared](https://safebet.ai/us/prediction-markets/prediction-market-fees/) - [Prices vs odds: how to convert](https://safebet.ai/us/prediction-markets/prediction-market-odds/) - [How we rank prediction markets](https://safebet.ai/us/prediction-markets/how-we-rank/)