On this page
Choose the market category, enter shares or trade amount and a price. The calculator applies Polymarket’s current published formula locally; it does not fetch a live market or submit an order.
Current category rates
- Crypto: 0.07
- Sports, Economics, Culture, Weather and Other / General: 0.05
- Finance, Politics, Mentions and Tech: 0.04
- Geopolitics: 0 — currently fee-free
The category selector uses these current published rates. Custom rate remains available only when you have an exact market parameter to enter.
Formula and example
fee = shares × fee rate × price × (1 − price). For 100 Crypto shares at 50¢, the estimate is 100 × 0.07 × 0.50 × 0.50 = 1.75 USDC. At the same price and share count, a 0.05 category estimates 1.25 USDC and a 0.04 category estimates 1.00 USDC.
What this estimate excludes
Spread, slippage, rebates, deposits, withdrawals, network, bridge, exchange, wallet and third-party costs are excluded. A maker selection returns zero because current official documentation says makers are not charged; it does not estimate a rebate.
Read a market page before relying on a number
Check the exact question, resolution rules and available market activity before using a calculator result for a real-world decision.
Frequently Asked Questions
Is the fee parameter a flat percentage of my trade amount?
No. The estimate uses shares × fee parameter × price × (1 − price), so the effective percentage changes with price.
Can a category assumption differ from a market setting?
Yes. Category values are general assumptions; use a verified market-specific parameter when available.