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Polymarket fee calculator

Enter a price and a size. The calculator applies the taker fee curve and shows your cost, payout and break-even probability.

Polymarket fee calculator illustration

The formula

Polymarket charges takers a fee that depends on the price. Makers, whose resting orders get filled, pay nothing. The rate is set per market in its fee schedule; the published sports rate is 0.05, and some markets are set to zero.

fee = shares × rate × price × (1 − price); break-even = price × (1 + rate × (1 − price))

s is shares, r the market’s rate and p the price as a fraction of $1.

Because of the price × (1 − price) term the fee is largest at 50¢ and shrinks toward 0¢ and $1. In dollars it is the same at 25¢ and 75¢, but as a share of what you pay it is three times heavier on the cheap side.

Worked example

Worked example: 100 shares at 50¢, sports rate 0.05

  1. Fee: 100 × 0.05 × 0.50 × 0.50 = $1.25 on $50 (2.5%)
  2. Break-even win probability: 51.25%
  3. For comparison, 100 shares at 20¢: fee $0.80 on $20 (4.0%)

The fee is largest in cents at 50¢, but heaviest as a share of cost on cheap shares.

Read the rate on the market you trade. Arbs reads each market’s fee schedule from Polymarket and nets it out before it calls a price an edge.

Frequently asked questions

Does Polymarket charge fees on sports?

Taker orders on most sports markets pay a fee at a rate set per market, 0.05 on the published sports schedule. Maker orders are free. Deposits and withdrawals carry no Polymarket fee, though your on-ramp may.

How is the Polymarket fee calculated?

shares × rate × price × (1 − price). At 50¢ with a 0.05 rate, that is 1.25¢ per share.

How do I avoid Polymarket fees?

Post a limit order that rests on the book instead of taking the best price. Makers pay no fee, but you risk not getting filled before the price moves.

What is my break-even probability after fees?

The price plus the fee per share. A 50¢ share at the 0.05 rate needs a 51.25% win rate to break even.

Read the guide: Polymarket fees explained for sports bettors

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