Platforms
Manifold Markets vs Polymarket
Manifold is play-money, Polymarket is real money. Both are useful, but for different reasons. Here is when to use each.
Manifold and Polymarket sit at opposite ends of the prediction market spectrum. Manifold uses play money (Mana) and lets anyone create markets on anything. Polymarket uses real USDC and curates markets carefully. Each design choice creates a very different product.
Play money vs real money
Manifold's currency, Mana, can't be cashed out. You start with M$1,000 free, earn more by trading well, and use it to bet on markets. Because there's no real money on the line, two things happen:
- The barrier to entry vanishes — anyone can sign up and play immediately.
- The price discipline weakens — there's less incentive to be exactly right.
Manifold's calibration is decent — within a few percentage points of true probability on average — but it's less sharp than Polymarket on the same questions. Real money focuses the mind.
User-generated markets
Manifold's biggest distinguishing feature: anyone can create a market. The platform has thousands of niche markets — "Will my friend get a job at Google by June?", "Will the next OpenAI release beat GPT-5?", "Will it rain in Berkeley tomorrow?" — that no real-money platform would ever list because the audience is too small.
For superforecasters, AI researchers, the rationalist community, and anyone interested in calibrating beliefs across many domains, this is hugely valuable. Polymarket can't match it because curating and resolving real-money markets at that volume is too expensive.
When to use each
- Use Manifold when: You want to practice probability calibration, you're interested in niche topics, you live somewhere Polymarket isn't available, or you just want to play.
- Use Polymarket when: You want real-money markets, deeper liquidity, or higher signal/noise on major events. Get started here.