BTC Up or Down odds, payouts and expected value
In Bitcoin Up or Down, a share's price in cents is the market's estimate of its chance of winning, and the price you pay decides both your payout and the win rate you need. This guide shows the maths with worked examples.
How Up and Down prices work
A share's price in cents is the market's chance of that side winning, because every share pays $1 if right and $0 if wrong. UP at 70¢ means roughly a 70% chance BTC finishes at or above the price to beat. UP and DOWN together add up to about $1, plus a small spread.
Three things move the price:
- Distance: how far BTC is above or below the price to beat.
- Time left: the same $30 lead is worth far more with 10 seconds left than with 5 minutes left.
- Volatility: when Bitcoin is jumping around, leads are less safe and prices stay nearer 50¢.
| Bet | Share price | Shares for $25 | Paid if right | Profit if right |
|---|---|---|---|---|
| UP | 75¢ | 33.33 | $33.33 | +$8.33 |
| DOWN | 27¢ | 92.59 | $92.59 | +$67.59 |
UP is the likely winner here, so it's expensive and pays a small profit. DOWN is cheap because it needs BTC to fall more than $30 in a minute. Neither is automatically the smart bet. It depends on whether you think the price is wrong.
Why prices swing so fast near the close
With little time left, BTC has less room to move, so even a small lead becomes very likely to hold. That's why a side can jump from 60¢ to 90¢ in the final 20 seconds of a round, and why one late tick across the price to beat can flip it straight back.
Payouts and break-even win rates
The price you pay sets both your payout and the win rate you need to break even. Shares = stake ÷ price, and each winning share pays $1. Buy at 60¢ and you need to be right more than 60% of the time to profit over many rounds, a little more once you count the spread and any fees.
| Share price | Break-even win rate | Paid if right | Profit if right | Multiple |
|---|---|---|---|---|
| 5¢ | 5% | $2,000.00 | +$1,900.00 | 20.00x |
| 10¢ | 10% | $1,000.00 | +$900.00 | 10.00x |
| 20¢ | 20% | $500.00 | +$400.00 | 5.00x |
| 25¢ | 25% | $400.00 | +$300.00 | 4.00x |
| 33¢ | 33% | $303.03 | +$203.03 | 3.03x |
| 40¢ | 40% | $250.00 | +$150.00 | 2.50x |
| 50¢ | 50% | $200.00 | +$100.00 | 2.00x |
| 60¢ | 60% | $166.67 | +$66.67 | 1.67x |
| 67¢ | 67% | $149.25 | +$49.25 | 1.49x |
| 75¢ | 75% | $133.33 | +$33.33 | 1.33x |
| 80¢ | 80% | $125.00 | +$25.00 | 1.25x |
| 90¢ | 90% | $111.11 | +$11.11 | 1.11x |
| 95¢ | 95% | $105.26 | +$5.26 | 1.05x |
Cheap shares pay big multiples but rarely win. Expensive shares win often but pay little. Over time, the price you pay matters more than how often you're right.
Expected value: how to tell a good bet from a bad one
A bet is good only if your chance of winning is higher than the price you pay. Expected value (EV) measures that: what a bet is worth on average if you repeated it many times.
EV = (your probability × payout) − stake
Say UP costs 60¢ and you believe UP wins 65% of the time. A $100 bet buys 166.67 shares. EV = 0.65 × $166.67 − $100 = +$8.33. If you only believe 55%, EV = 0.55 × $166.67 − $100 = −$8.33. Practising here helps you check whether your estimates are any better than the model's.
Fees on real BTC Up or Down markets
Real markets charge trading fees, and on short windows they can be bigger than your edge. Kalshi's taker fee on its 15-minute Bitcoin series has been 0.07 × contracts × price × (1 − price). That's about 1.75¢ per contract at a 50¢ price and about 0.63¢ at 90¢, while orders that rest on the book and fill later have paid no fee (source). Polymarket publishes its own fee schedule, which can differ by market.
60sBTC has no fees, but it does build a 2¢ spread into every quote so trading in and out still costs something, as it would on a real order book. Fees change, so always check a platform's current schedule.