A situation where prices across bookmakers allow a guaranteed profit regardless of outcome (rare and often limited).

The total amount of money you set aside for betting.

The operator offering odds you can bet on.

How your odds compare to the closing odds at event start; often used to judge betting quality.

Your estimated advantage over the bookmaker price, usually derived from fair odds vs offered odds.

The long-run average outcome of a bet. Positive EV means favorable expectancy over time.

Odds that reflect the “true” probability (without bookmaker margin), based on a reference model/market estimate.

A points/goals adjustment applied to balance teams (common in basketball, football, etc.).

The probability suggested by odds (e.g., decimal odds 2.00 imply 50%).

A staking formula that suggests bet size based on edge and odds (often used in reduced form for safety).

The offered price/odds or point total/spread for a market.

How odds or lines shift over time as money and information change the market.

How much money a market can take without moving the odds significantly.

A specific betting proposition (moneyline, total, spread, player props, etc.).

A bet on who wins (no spread/handicap).

When odds shorten (price decreases), often indicating increased market support for that side.

The bookmaker’s built-in profit margin embedded in the odds.

Profit divided by amount staked, usually shown as a percentage.

Action believed to come from skilled bettors that can influence line movement.

The amount you bet.

Betting on whether the combined score exceeds or falls below a line.

A standardized bet size used to track performance independent of bankroll size.

A bet where the offered odds are higher than your estimated fair odds, implying positive EV.

Natural swings in results in the short term, even with a good strategy.