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Sports Betting Math, Explained
Agatha's record since August 24, 2026: 2,630 graded picks, 1,531-1,095-4, a 58.3% win rate against the 59.4% the prices needed, -58.96u at one unit each (-2.3% ROI). See the track record.
Each guide works its math through with numbers from that record, and each one links the calculator that does the sums on your own bets.
Guides
Honest answers to the questions that decide whether betting works for you.
- What Is Closing Line Value (CLV)?Why the price you get says more than a winning week, how to measure it, and what Agatha's own picks show.
- Are Parlays Worth It? The Math of Stacking LegsHow each extra leg multiplies the book's margin, worked through with real prices and every parlay Agatha's graded picks could have made.
- How Long Do Losing Streaks Last?The math of losing runs and drawdowns at a given win rate, next to the longest streaks and the deepest drawdown in Agatha's own record.
Reference
The words and the rules behind every pick on this site.
- Sports Betting GlossaryShort definitions of the betting terms on this site, from odds formats and hold to Agatha's own words: lean, edge, seal and receipt.
- How Agatha Grades Every PickThe settlement rulebook behind Agatha's public record: wins, losses, pushes and voids, sport by sport, taken from the grader itself.
- How Agatha WorksHow the models are built and validated, what her confidence number means, and the rules the record lives by.
- How Sealing WorksHow every pick is sealed before its game starts, and how to check any receipt yourself.
Calculators
Do the math on your own bets, free.
- Parlay CalculatorPrice any parlay in any odds format, settle pushes and voids the way the books do, and see what the extra legs cost against fair odds.
- Odds ConverterTurn American, decimal, fractional or percentage odds into every other format, with the break-even win rate each price needs.
- No-Vig Fair Odds CalculatorRemove the book's margin from a two-way or three-way market to get fair odds, the vig and the hold, by three methods.
- Hedge CalculatorFind the hedge stake for an equal result or your stake back, see what each outcome nets, and see what the hedge itself costs.
- Kelly Criterion CalculatorSize a bet with full or fractional Kelly, and see how fast the answer changes when your win probability is a little too high.
- Closing Line Value CalculatorCompare the price you took with the closing price, with or without the vig, for one bet or a whole list at once.