Academy
Short lessons on odds, staking and trading — plain English, no jargon.
The lessons build on each other, so they are numbered. Start at the top.
013 min read
How betting odds work
Decimal, fractional and American odds all say the same thing: how likely something is, and what you get paid if it happens. Here is how to read them.
024 min read
How bookmakers make their odds
Odds do not come from a crystal ball. They start with a model, get a margin added, and then move with the money. Here is the life of a price.
034 min read
Expected value, variance and why results lie to you
A winning bet can be a bad bet, and a losing bet can be a good one. The way to tell them apart is expected value — and the reason it takes so long to see is variance.
045 min read
What is the Kelly criterion?
A 1956 formula from a Bell Labs physicist tells you exactly how much to stake when you have an edge. Here is what it says, how to use it, and why most people use half of it.
055 min read
Staking methods compared: flat, percentage, Kelly and the ones to avoid
Picking the bet is only half the job. How much you stake decides whether an edge turns into profit or into a blown bankroll. The main methods, side by side.
064 min read
Betting exchanges: back, lay and trading
On an exchange you bet against other people, not a bookmaker. That opens two things a bookmaker never offers: betting on something to lose, and trading a position like a share.