Learn the language of value betting
Short, honest explainers for every concept we use on TipsAudit — fair odds, closing line value, bookmaker margin and the maths that decides whether a bettor wins long-term. No hype, no promises: just how the numbers actually work.
Fair odds
Fair odds are what a bet would pay if the bookmaker took no cut: the fair probability, estimated from the sharpest market, turned into a price with the margin removed.
Closing Line Value (CLV)
CLV measures whether you beat the final market price. It is one of the strongest public signs of real skill, because it can be checked long before profit means anything.
Bookmaker margin (vig) and devigging
The margin is the bookmaker's built-in cut on every market. Devigging removes it to reveal the probabilities the book actually believes.
Expected value (EV)
Expected value is the long-run average result of a bet: probability times payout, minus the stake. Positive EV is the only reason to ever place a bet.
Value bet
A value bet is a price above the fair probability — not a likely winner. The favourite can be terrible value; a longshot can be excellent value.
Sharp vs soft bookmakers
Sharp books welcome winners and their prices are close to the truth. Soft books ban winners and their prices drift — that drift is where value hides.
The closing line
The closing line is the final odds before kick-off — the market's most informed price, and the benchmark every serious bettor measures against.
Kelly criterion
The Kelly criterion sizes bets in proportion to your edge. It maximises long-term growth — and shows why betting without an edge guarantees ruin.
Why win rate misleads
A 67% win rate can lose money and a 35% win rate can print it. Win rate without odds is the most seductive meaningless number in betting.
Longshot bias
Bookmakers systematically overprice longshots because bettors love them. The margin is not spread evenly — outsiders carry most of it.
Line movement
Odds move because information and sharp money arrive. Reading why a line moved tells you more than the movement itself.
Variance and sample size
Short-term results are mostly noise. Hundreds of bets are needed before profit says anything — which is why monthly ROI screenshots mean nothing.