Player props
The market with the biggest margin, and the softest lines.
Free tools and plain math for sports bettors
Price it. Size it. Track it.
Calculators and guides for bettors who want to beat the price, not chase picks: take the vig out of any line, size each bet to your bankroll, and see whether you're beating the closing line.
- No picks, no tipsters
- Every number worked out
- Free, nothing to sign up for
The calculators
They run in your browser; nothing you type leaves the page.
Prop odds & edge
Take the vig out of an over/under to see the fair odds, turn your projection into a chance, and see the edge, the EV a $100 bet and the Kelly stake. Shop up to six books on the same line.
Price a propBet sizing & streaks
Your bet size from the bankroll, flat units or a fraction of Kelly, the losing streak to expect over a season, and a thousand simulated seasons of how the bankroll could run.
Size your betsProp bet tracker
Log each prop with its price and the closing price: your record, units, ROI and CLV by sport, market and side, and whether the results are skill or luck. Kept in your browser only.
Track your betsStart here: one bet, three steps
The order a sharp bettor works in, with the guide for each.
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Price the bet
Is the number better than the real chance? Find out before you look at the matchup twice.
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Size the stake
How much of the bankroll this bet deserves, and the losing streak you should expect anyway.
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Judge the result
Not by last weekend: by the price you got against the closing line, over hundreds of bets.
By topic
MLB: run lines and dogs
When -1.5 beats the moneyline, and when the underdog is the price.
Reading the market
Line moves, public money and the price at kickoff.
Four books worth reading
No system, just the arithmetic of lines and stakes.
The Logic of Sports Betting
Ed Miller & Matthew Davidow
How lines are made, moved and beaten. Read this one first.
View on Amazon
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Bankroll
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Bet with your head. Most bettors lose over time, and nothing here is a sure thing. Bet only where it's legal for you, only money you can afford to lose. If it stops being fun, call or text 1-800-MY-RESET (1-800-697-3738), free and confidential.