Kelly criterion calculator
Worked example
At -110 the profit on a win is 0.909 per 1 staked. With an estimated win chance of 56% the expected value is +6.9% of the stake, and the full Kelly fraction is 6.9% / 90.9% = 7.6% of bankroll. A quarter Kelly is 1.9%.
How it works
The Kelly fraction is the expected value per unit divided by the profit per unit on a win. It is zero when the expected value is zero or negative, and the calculator says so instead of showing a negative stake.
Kelly assumes your win chance is exactly right. Estimates rarely are, which is why some people use a fraction such as a quarter or a half. ArchivePicks does not say what you should stake or which side to take.
Frequently asked questions
What is the Kelly criterion?
It is a formula for the fraction of a bankroll to stake on a bet, given the price and an estimate of the win chance. It is the expected value per unit divided by the profit per unit on a win.
What is quarter Kelly?
Quarter Kelly is one quarter of the full Kelly fraction. Some people use a fraction of Kelly because the formula assumes the win chance estimate is exactly right.
Why does the calculator say to stake nothing?
When your estimated win chance is at or below what the price implies, the expected value is not positive and the Kelly fraction is zero.
Does ArchivePicks recommend a stake?
No. This is arithmetic on numbers you enter. ArchivePicks does not take bets, recommend stakes or say which side to take.
Related
- Expected value (EV) calculator
- Implied probability calculator
- Parlay calculator: combined odds and payout
- All odds calculators
- Kelly criterion in the Glossary
For information only. ArchivePicks does not take bets and does not tell you which side to take.