Two platforms now run the prediction-market world: Kalshi and Polymarket together hold about 97.5% of all volume. Everything else — Manifold, PredictIt, Metaculus — serves a narrower purpose. This guide compares the platforms that actually matter in 2026 on the things that decide where you should trade: who can legally use them, what they cost, what they're good at, and which tools plug into them.
If you already know you want Polymarket, skip to the full tools directory. If you're still choosing a platform, start here.
Quick pick
- Want regulated, U.S.-legal event contracts? → Kalshi
- Want the deepest liquidity and the widest range of markets? → Polymarket
- Want to practice forecasting with no money at risk? → Manifold or Metaculus
- Only care about U.S. politics? → PredictIt (but mind the fees)
The two that dominate
Polymarket — biggest by volume, crypto-native
Polymarket is the largest prediction market in the world by volume — it processed over $3.5 billion during the 2024 U.S. presidential election alone. It runs on-chain (USDC on Polygon), which means deep liquidity, fast-moving markets, and the broadest catalog: politics, crypto, sports, world events, culture.
Fees (2026): Polymarket is no longer fee-free. Since March 30, 2026 it charges category-based taker fees that peak near the 50/50 price point — roughly 1.8% on crypto markets, 0.75% on sports, and geopolitics and world events stay free. Resting limit orders (makers) pay nothing and can earn a rebate. There are no deposit or withdrawal fees on Polymarket itself. Full breakdown in our Polymarket fees guide. Best for: active traders who want the most markets and the most liquidity — and the richest ecosystem of third-party tools (more on that below).Kalshi — the regulated one
Kalshi is the only fully CFTC-regulated prediction market that's legal for all U.S. residents, with USD funding and a mainstream mobile app. It leads on regulated U.S. event contracts and on sports liquidity for American users.
Fees: Kalshi uses a P × (1−P) taker-fee curve that peaks around 1.75% at the 50-cent price point and drops sharply toward the extremes, with no account or settlement fees. Best for: U.S. traders who want a regulated, dollar-based platform with simple onboarding.Deciding between these two specifically? We break it down in Polymarket vs Kalshi.
The alternatives worth knowing
Manifold Markets — play money, zero fees
Manifold uses play money, so there are no fees and no financial-risk gating — which is exactly why it has the largest, most eclectic catalog of markets. It's the best place to practice reading a market or run a community forecast without risking real capital.
PredictIt — politics only, expensive
PredictIt is real-money and focused on U.S. politics, but the costs are steep: a 10% commission on profits plus a 5% withdrawal fee (combined drag over 14% on a winning position). As of early 2026 it still operates under regulatory uncertainty that has thinned its volume.
Metaculus — forecasting, not trading
Metaculus isn't a market at all — it's a forecasting platform for researchers and analysts who care about calibration and accuracy rather than payouts. No money changes hands. Great for sharpening your judgment.
The part most comparisons miss: tools
Picking a platform is only half the decision. The other half is what you can bolt onto it. This is where Polymarket pulls ahead — its open, on-chain data has produced by far the deepest ecosystem of third-party tools:
- Analytics dashboards — market depth, probability history, and cross-market views
- Portfolio trackers — live P&L and position tracking across wallets
- Trading bots — automated and copy-trading execution
- Alerts — whale moves and price-swing notifications
- Arbitrage scanners — price gaps between Polymarket and Kalshi
Kalshi has a smaller but growing tool set; Manifold and Metaculus are largely self-contained. If tooling matters to how you trade, Polymarket is the platform with the most to plug into — and yesornotool ranks 100+ of those tools, re-checked every week by real traders.
Bottom line
For most people it comes down to two: Kalshi if you want regulated and simple, Polymarket if you want depth, breadth, and the best tools. The alternatives fill real niches — Manifold and Metaculus for practice, PredictIt for politics — but they're not where the volume is.
Once you've picked, browse the tools that make each platform better →
