Kalshi (CFTC-regulated, US-legal), Manifold Markets (free practice), PredictIt (political, US-legal), and Metaculus — compared by liquidity, legality, fees, and use case.
| Platform | US Legal | Real Money | Liquidity | Fees | Best For |
|---|---|---|---|---|---|
| Polymarket | ❌ Blocked | ✅ USDC | Highest ($500M+/mo) | 2% of winnings | Non-US serious traders |
| Kalshi | ✅ CFTC-reg | ✅ USD | Medium ($50M+/mo) | ~1% round-trip | US traders wanting legal access |
| Manifold Markets | ✅ | ❌ Play money | Low (fictional) | Free | Learning & practice |
| PredictIt | ✅ Limited | ✅ USD | Low–Medium | 10% of winnings | US political markets ($850 cap) |
| Metaculus | ✅ | ❌ No money | N/A | Free | Long-range research & base rates |
Polymarket is the largest decentralized prediction market by volume, but it has limitations: US traders face restrictions, certain event categories are thin, and liquidity varies widely across markets. Alternative platforms fill different niches — regulated US access (Kalshi), play-money experimentation (Manifold), or academic forecasting (Metaculus).
Kalshi is the first CFTC-regulated prediction market exchange in the US, launched in 2021. It offers legally compliant event contracts to US residents — something Polymarket cannot.
Manifold uses fictional "mana" currency — no real money at stake. It's ideal for learning prediction market mechanics, testing forecasting skills, and discovering early alpha on events before real money markets exist.
Metaculus is a forecasting platform (not a trading market) where participants make probability predictions on future events. It has a track record and calibration data going back to 2015 — useful for finding well-researched base rates on complex topics.
PredictIt is a political prediction market that has operated in the US under a CFTC no-action letter since 2014. It focuses on US political events — elections, legislation, White House. Maximum account position of $850 per market.
Professional arbitrageurs use multiple platforms simultaneously to capture price discrepancies between Polymarket and Kalshi for the same event (see the Arbitrage guide).
Poly-Sim Score, Hall of Whales, Ripple Effect and more — all free, all built specifically for Polymarket traders.
Explore All Tools →To trade on Polymarket you need USDC on the Polygon network. The simplest path: sign up on Kraken, buy USDC with a bank transfer (ACH/SEPA — free), withdraw USDC on Polygon (~$0.90 flat), and connect your MetaMask wallet to Polymarket. Full step-by-step instructions in our exchange funding guide.