How Polymarket pricing works

Price is a probability

Every Polymarket market resolves to one of two outcomes, and the winning side pays out $1 per share. That makes the current price a direct read of the crowd’s odds: a share trading at 65¢ means the market thinks that outcome has roughly a 65% chance of happening. There is no separate “probability” to compute — the price already is the probability, which is what makes these markets unusually clean to trade systematically.

UP and DOWN, side by side

Most Polymarket markets Gogobots trades are framed as a pair: will an asset be UP or DOWN relative to a reference price when the market resolves. The two sides are complementary — their prices always sum to roughly $1 — so trading UP and trading DOWN are really the same decision seen from opposite ends.

Five market durations

Markets come in several fixed lengths, and the one you pick changes the character of a strategy:

• 5 minutes — fastest feedback, noisiest price action
• 15 minutes — still quick, slightly smoother
• 1 hour — a middle ground between speed and stability
• 4 hours — slower-moving, more room for a trend to develop
• 24 hours — the longest window, closest to a daily view

How a contract behaves over its life

A market’s price does not move the same way throughout its life. Early on, price reacts mostly to the same signals that move the underlying asset. As the deadline approaches, that stops being enough — the market has to converge toward 0 or $1 no matter what happens next, simply because time is running out to prove itself wrong. Strategies that ignore this tend to get whipsawed right before resolution; the backtester’s per-trade timing data is there partly so you can see whether your entries and exits already account for it.

Trading costs are not flat

Polymarket charges a small taker fee on each trade, and that fee is not constant — it is close to zero near the extremes (very likely or very unlikely outcomes) and largest around 50¢, where the outcome is most uncertain. A strategy that trades often around coin-flip prices pays more in fees than one that waits for more one-sided setups. This is baked into the backtester’s results automatically, so the numbers you see already reflect it.