Prediction markets — how we read each one

Four of the prediction markets these boards read prices from, plus Hyperliquid, which the board watches but does not price, and what we found in each one’s public API — including the parts that make one look worse. We are not affiliated with any of them and none of these pages carry referral links.

Polymarket

The largest crypto-settled prediction market, on Polygon, settled through UMA.

Fees. A per-market taker rate Polymarket publishes as `feeSchedule.rate`, applied as rate × p × (1−p).

Worth knowing. Tags are absent from the Gamma response unless `include_tag=true` is passed — and without them the fee model silently falls back to the maximum rate.

Kalshi

A CFTC-regulated US exchange, settled in dollars.

Fees. Published as min(7¢, 7% × p × (1−p)) per contract — about 2¢ across almost the whole price range, and charged on both sides.

Worth knowing. Weather ticker naming is inconsistent — KXHIGHMIA and KXHIGHLAX carry no “T” while KXHIGHTDAL and KXHIGHTSEA do — so tickers must be enumerated, never constructed.

Predict.fun

A Blast-based prediction market whose contracts mirror much of Polymarket’s structure.

Fees. Publishes 200bps taker, read per market rather than assumed..

Worth knowing. The `title` field is the OUTCOME label — “No change”, “25 bps increase” — while `question` carries the actual question. Rendering `title` puts two words beside a full sentence from another prediction market.

Limitless

A Base-network prediction market that tags many of its contracts against a Polymarket counterpart.

Fees. Not published anywhere in its API.

Worth knowing. A group child’s title is just the outcome label (“No change”); the full question lives on the parent group.

Hyperliquid

A perpetuals exchange that added binary outcome markets (HIP-4) in May 2026.

Fees. Not modelled here, because nothing on this site is paired against it..

Worth knowing. The three markets with a real-world analogue — Fed policy rate — ship an EMPTY description, so the API states neither which meeting they resolve against nor whether “Decrease” means any cut or exactly 25bp. Both unknowns are the kind that lose both legs of a hedge, so it stays watched rather than paired until Hyperliquid publishes resolution text.