Reference documents you can keep
The betting maths we explain across the site, packaged as reference documents in PDF and Word. Open any entry to see exactly what it covers before you download.
Please note: these are educational reference documents (PDF / Word), not an app or a betting product to download. WagerLex takes no wagers, publishes no picks, and runs no affiliate links.
How Big Should a Betting Unit Be? A Bankroll and Kelly Staking Reference (2026)
How big should a betting unit be, and what does the Kelly criterion actually tell you to stake? This free reference (PDF/Word) covers unit sizing, flat staking, and the Kelly formula with worked numbers — including why most who use it bet a fraction. Editorial reference, not financial advice.
What Is the Vig on -110 and How Do You Remove It? An Implied-Probability Conversion Reference (2026)
What is the vig on a -110 bet, and how do you convert a price into a fair probability? This free reference (PDF/Word) gives the American and decimal conversion formulas, worked no-vig examples, and the overround-versus-hold distinction — all arithmetic you can verify. Editorial reference only.
How Does a Sportsbook Actually Make Money? Hold, Balanced Books and the Vig, Explained (2026)
How does a sportsbook actually make money, and is it really just 'the house always wins'? This free reference (PDF/Word) walks through hold, the balanced-book ideal, why real books carry positions, and where the margin comes from — in arithmetic you can check. Editorial reference, not a betting product.
21+ · Educational reference only. If gambling is affecting your life, support is available at 1-800-GAMBLER.