How to use the contract calculator
- Price — the price of one "Yes" contract in cents (1¢–99¢). For a "No" position, use the "No" price.
- Stake — how much you want to spend.
The calculator shows how many whole contracts you can buy, the probability the price implies, what you'd receive if the contract settles "Yes", and your profit on the money actually spent. The note underneath shows the amount spent and any unused change.
The maths
- Contracts = stake ÷ price (rounded down)
- Implied probability = price ÷ $1
- Payout if right = contracts × $1
- Money spent = contracts × price (any remainder stays in your account)
- Profit if right = payout − money spent
Example: $100 at 62¢ buys 161 contracts. That costs $99.82, and the unused 18¢ stays in your account. If you're right, you receive $161 — a profit of $61.18 before fees. If you're wrong, you lose the $99.82 you spent. Either way your final balance includes the 18¢.
Including the fee in your budget
On Kalshi's standard taker fee, 161 contracts at 62¢ would cost $99.82 plus a $2.66 fee — $102.48, over budget. With fees included, $100 buys 157 contracts: $97.34 for the contracts plus a $2.59 fee = $99.93. If you're right you receive $157, a profit of about $57.07.
Payout at every price
| Price | Implied chance | Profit per $1 risked if right | Contracts for $100 (before fees) |
|---|---|---|---|
| 10¢ | 10% | $9.00 | 1,000 |
| 25¢ | 25% | $3.00 | 400 |
| 50¢ | 50% | $1.00 | 200 |
| 62¢ | 62% | $0.61 | 161 |
| 75¢ | 75% | $0.33 | 133 |
| 90¢ | 90% | $0.11 | 111 |
Selling early: an example
You bought 100 contracts at 40¢ ($40). News breaks and the price jumps to 70¢. Selling now returns $70 — a $30 profit before fees — without waiting for settlement. If instead the price falls to 20¢, selling caps your loss at $20. Some platforms charge a fee again when you close early.
What the calculator doesn't show
- Fees — up to about 1.75¢ per contract at a 50¢ price on Kalshi and Polymarket US's standard schedules, nothing on Novig's pre-game trades, and more on payout-based fees. See the fee calculator and our prediction market fees guide.
- The spread — the price you pay may be a cent or two above the midpoint. See order books and limit orders.
- Selling early — you can usually sell before settlement at the current price, locking in a profit or cutting a loss.
Want to know if the trade is actually good value? Try the edge calculator, and read implied probability.
