⚡ Prediction Market Tool

Polymarket vs Kalshi
Arbitrage Calculator

Find guaranteed profit opportunities when prediction markets disagree on the same event. Enter prices, we'll do the math.

🧠 How Prediction Market Arbitrage Works
1

Markets Disagree

Polymarket prices YES at 62¢ but Kalshi prices NO at 45¢ for the same event

2

Buy Both Sides

Buy YES on one platform and NO on the other. Total cost: 62¢ + 45¢ = $1.07... wait, that's no good. But 62¢ + 35¢ = 97¢

3

Guaranteed Profit

One side always pays $1. You paid 97¢. That's 3¢ guaranteed profit per share, no matter what happens.

🧮 Arbitrage Calculator
Try an example:
Polymarket
¢
¢
VS
Kalshi
¢
¢
$
📊 Results
Popular Arbitrage Scenarios

Click any scenario to load it into the calculator. Prices are examples — always verify current prices on each platform before trading.

🇺🇸 Will candidate X win the election?
Polymarket YES 62¢ · Kalshi YES 65¢
3% ARB
📈 Will BTC hit $150K by June?
Polymarket YES 45¢ · Kalshi YES 48¢
3% ARB
🌡️ Will global temp record break in 2026?
Polymarket YES 72¢ · Kalshi YES 75¢
3% ARB
⚽ Will England win the World Cup?
Polymarket YES 50¢ · Kalshi YES 52¢
No arb
💡 Arbitrage Strategy Tips
Speed matters
Prediction market arbs are fleeting. Prices shift within minutes as traders spot the same gaps. Have accounts funded on both platforms before you start scanning.
Watch the fees
Polymarket charges no trading fees but has blockchain gas costs. Kalshi charges fees on winning trades (varies by market). A 2% arb might disappear after fees. This calculator shows pre-fee profit — always factor in platform costs.
Liquidity is king
An arb means nothing if you can't fill your order at the displayed price. Check order book depth on both platforms. Thin markets = slippage = your arb evaporates.
Capital lock-up
Your money is locked until the market resolves. A 3% arb on a market that resolves in 6 months is only ~6% annualized. Compare to risk-free alternatives like stablecoins or T-bills.
Resolution risk
Different platforms may resolve the "same" event differently due to different resolution criteria. Always read both sets of rules. Edge case resolutions have burned arb traders before.
❓ FAQ
What is prediction market arbitrage?
Arbitrage is when you exploit price differences between two markets for a guaranteed profit. If Polymarket prices an event at 62% YES and Kalshi prices the same event at 65% YES, the NO prices are 38¢ and 35¢ respectively. Buying YES on Polymarket (62¢) and NO on Kalshi (35¢) costs 97¢ total, but one side is guaranteed to pay $1 — a 3¢ risk-free profit per share.
Is prediction market arbitrage legal?
In most jurisdictions, yes. Polymarket operates on blockchain (Polygon) and is available globally (with some restrictions). Kalshi is a CFTC-regulated exchange in the US. Check your local regulations, especially regarding event contracts and prediction markets.
How much can I make from prediction market arbitrage?
Typical arbs are 1-5% per trade. On a $10,000 bankroll, a 3% arb nets $300. The key is volume and speed — serious arb traders automate scanning and execution, running many small arbs per day.
What's the difference between Polymarket and Kalshi?
Polymarket is a decentralized prediction market on Polygon (crypto-native, USDC deposits, global access). Kalshi is a centralized, CFTC-regulated exchange (USD deposits, US-focused). Different user bases = different prices = arbitrage opportunities.
Can I use this calculator for other prediction markets?
Absolutely. The math works for any two binary outcome markets: PredictIt, Manifold, Metaculus (if they add real-money markets), or even sports betting exchanges. Just enter the YES prices from each platform.