Guides
How beating a price actually works
The guides
Start here
Value betting explained
What a value bet is, where the probability estimate comes from, how to find one, how much to stake, and the limits nobody selling software mentions.
Surebets
Arbitrage betting explained
How backing every outcome across different books locks a profit — and the seven checks that separate a real arbitrage from an expensive illusion.
The method
No-vig odds
Why a bookmaker's price is not a probability, and the five ways to remove the margin — proportional, Shin, power, odds-ratio and additive.
The proof
Closing line value
How to tell whether your edge was real without waiting hundreds of bets for profit to say so. Including how to calculate CLV without flattering yourself.
Reference
Betting glossary
Vig, overround, de-vig, CLV, Kelly, surebet, middle, steam, palp — every term used on this site, defined once.
The premise they share
Bookmakers do not agree with each other, and one of them is much more likely to be right. A book with thin margins, high limits and no habit of banning winners cannot afford an inaccurate line; a recreational book setting prices to balance its own customers can. The gap between the two is where all of this lives.
There are exactly two ways to convert that gap into money:
- Value betting — take the sharp line, remove its margin, and bet anywhere a softer book is offering more than the resulting fair price. An edge over many bets, with real variance around it.
- Arbitrage — when books disagree enough that every outcome can be backed profitably, take all of them. Locked on a single fixture, but you need every leg placed and the checks have to be right.
Both are arithmetic on public prices. Neither predicts anything. If you want to see the arithmetic running on live data, the odds comparison board is public and the calculators need no account.
For research, not betting advice. Positive expected value is an edge across many bets, never a prediction about one. Bet only what you can afford to lose. 18+.