American odds in betting

American odds use a plus or minus sign against a base of 100. A price of +150 wins 150 for every 100 staked; -150 means you must risk 150 to win 100.

The sign tells you which side of even money the selection sits. Positive numbers are underdogs and show profit on a 100-unit stake; negative numbers are favourites and show the stake needed to profit 100. The format is standard on NBA, NFL, MLB and NHL markets, which matters more every year as Nigerian bettors move into American sports.

Positive: decimal = (odds / 100) + 1. Negative: decimal = (100 / |odds|) + 1.

The Lakers are -180 and the Suns +155. A ₦18,000 bet on the Lakers profits ₦10,000; a ₦10,000 bet on the Suns profits ₦15,500. Converting to decimals gives 1.556 and 2.55, which sum to an implied 64.3% + 39.2% = 103.5% — the 3.5 points above 100 is the bookmaker margin on that game.

NBA and NFL lines move faster and are priced more sharply than most football markets. If you cannot read -110 as 1.909 instantly, you will misjudge whether a boosted price or a teaser is actually generous.

Nigerian bettors backing NBA overnight often see American odds on international feeds and decimals in their own app. Convert before comparing, or a -105 line that looks worse than 1.95 will slip past you when it is actually better.

• Reading -110 as a small number and assuming a small edge; it implies 52.4%, which is why beating spreads is hard.
• Treating +100 and -100 as different prices — both are evens, 2.00 in decimals.
• Forgetting that negative odds mean the stake, not the profit, so a -250 bet risks far more than it returns.