Understanding American Odds (+150 / -110)

By the Bettor Alerts team · Updated May 1, 2026

American odds explained: what plus and minus prices mean, how to convert them to implied probability, and how to find the best price.

Plus and minus

A negative price (e.g. -110) is the amount you must risk to win $100. A positive price (e.g. +150) is the amount you win on a $100 stake. -110 means risk $110 to win $100; +150 means risk $100 to win $150.

The favorite has the minus price; the underdog has the plus price.

Implied probability and shopping for the best line

Every price implies a probability. -110 implies about 52.4%; +150 implies about 40%. Comparing the implied probability to your own estimate is the basis of finding value.

Because different sportsbooks post different numbers, shopping for the best available price on every bet is one of the simplest, highest-ROI habits in betting. Bettor Alerts shows the best line across books on every game.

Put it into practice

See these concepts live: compare odds and line movement on NBA, NFL, and MLB odds, or get real-time alerts with the Bettor Alerts app. More in our betting guides.