MLB Moneyline: arbitrage calculator
- Market
- 2-way
- Typical overround
- 3%–5%
- Sample arbitrage return
- -1.92%
- Profit on every outcome
- -1.92
- Total stake
- 100.00
- Sum of implied probabilities
- 101.96%
| Leg | Odds used | Effective odds | Stake |
|---|---|---|---|
| Back Favorite | 1.710 | 1.710 | 57.36 |
| Back Underdog | 2.300 | 2.300 | 42.64 |
| If this wins | Legs that pay | Gross return | Commission | Net profit |
|---|---|---|---|---|
| Favorite | Favorite | 98.08 | 0.00 | -1.92 |
| Underdog | Underdog | 98.08 | 0.00 | -1.92 |
No arbitrage: -1.92% return
MLB moneylines depend heavily on the listed starting pitcher; check whether a book voids or re-prices the bet if the pitcher changes, because settlement rules differ.
Market structure
MLB Moneyline has 2 outcomes (
Favorite, Underdog). Bookmakers typically price it with an overround between 3% and
5%. For an arbitrage you need prices from at least two books whose implied probabilities, taken at the best price per outcome, add up to less than 100%.
Worked example
Two books quote 1.67 / 2.30 and 1.71 / 2.25. Taking the best price for each outcome (1.71 / 2.30) gives an implied sum of 101.96%. Arbitrage: no, return -1.92%. The calculator above is pre-filled with those best prices; the stakes for 100 in total are 57.36 / 42.64.
| Outcome | Book A | Book B | Best | Stake of 100 |
|---|---|---|---|---|
| Favorite | 1.67 | 1.71 | 1.71 | 57.36 |
| Underdog | 2.30 | 2.25 | 2.30 | 42.64 |
Two-way specifics
Two-way markets are the simplest to arbitrage: two prices, two stakes, one check that the implied probabilities sum below 100%. Watch for different settlement rules between books (retirements, postponements).
Frequently asked questions
How many legs does a MLB Moneyline arbitrage need?
One per outcome: 2 legs covering Favorite, Underdog. Every outcome must be backed for the position to profit whatever happens.
How large is the overround in MLB Moneyline?
Typically 3% to 5% at a single book. An arbitrage needs the best prices across books to sum below 100%, so the gap between books has to exceed the margin.
Is the worked example on this page a real arbitrage?
The sample prices give an implied sum of 101.96% at the best price per outcome (arbitrage: no). They are illustrative; live prices change constantly.
What can go wrong with an arbitrage across 2 outcomes?
A leg not being available at the assumed price, a void or push on one leg, different settlement rules between books, and stake limits that stop you placing the full amount.