How to Read Odds: Format Conversion & Implied Probability
Three ways to write it, one price—converting is how you actually read international lines
The three formats side by side
| Format | Notation | Meaning |
|---|---|---|
| Decimal (European) | 1.95 | Bet 1 to return 1.95 (stake included). Standard in Taiwan Sports Lottery and across Europe |
| Hong Kong | 0.95 | Pure profit multiplier = decimal odds − 1 |
| American | −110 / +150 | Negative: how much you stake to win 100; positive: how much you win on a 100 stake |
Don't want to do the math? Use the odds converter—it gives you the implied probability too.
Implied probability and the vig
Implied probability = 1÷decimal odds. When both sides of a game are priced at 1.909 (American −110): 52.4% + 52.4% = 104.8%, and the 4.8% above 100% is the vig (juice). Only after removing the vig (devigging) do you get the market's true estimate—which is exactly why "I've got it at 53%, so 1.909 is a buy" isn't enough: 53% is barely above the 52.4% implied, and once you account for estimation error there's almost no edge left.
Why this matters
Taiwan Sports Lottery odds are generally lower than international books (a heavier vig), so knowing how to convert and devig is what lets you spot the price gap for the same game across different markets and judge whether the price you're getting is any good. The "market anchor" section in every analysis on Sports Radar is the devigged implied probability.
Frequently Asked Questions
What do American odds of -110 mean?
You stake 110 to win 100 (total return 210). In decimal that's 1.909, an implied probability of about 52.4%.
How do I calculate implied probability?
1÷decimal odds. Example: 1.95 → 51.3%. Note that this includes the vig, so the two sides add up to more than 100%.
What is the vig?
The bookmaker's built-in commission baked into the odds. It's the amount by which both sides' implied probabilities add up to more than 100%—typically 4-7%.