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Betting calculators · Lines from 6 sportsbooks · Checked Tue 12:07 PM ET
Odds converterParlayHedgeExpected valueBet sizeTeaserRound robin
Betting calculators · 6 sportsbooks · Tue 12:07 PM

Bet size calculator

How much to stake when you think you have an edge. Enter the price, the chance you believe and your bankroll: the Kelly rule sizes the bet, and the quarter of it most bettors actually use.

How much to stake when you think you have an edge. Enter the price, the chance you believe and your bankroll: the Kelly rule sizes the bet, and the quarter of it most bettors actually use.

Odds converterParlayHedgeExpected valueBet sizeTeaserRound robin
Loaded
Colts at Steelers, Sun 1:00 PM · Colts to win at BetMGM
Worth per $100
−$2.32
Edge
-2.3%
Price that breaks even
+125
Kelly bet size
0.0%

At +120, the Colts cost $2.32 on every $100 on average, if 44.4% is right. A negative edge says not to bet at all.

Bet size at three bankrolls

Full Kelly and the quarter most bettors actually use
Bankroll
Full Kelly
Quarter Kelly
$500
$0.00
$0.00
$2,000
$0.00
$0.00
$10,000
$0.00
$0.00

The Kelly rule stakes a share of the bankroll equal to the edge divided by the odds. Most bettors use a quarter of it, because the chance going in is an estimate. 21+, where legal. Gambling problem? Call 1-800-GAMBLER.

Best Bets · Thursday mornings
The three widest gaps on the weekend card, in your inbox by 10.

Plus how the numbers moved since they opened, and which books held the best price. Free.

More calculators

Odds converterAny price in every format, with the book's cut taken outParlay calculatorWhat two to ten legs pay, and the true odds of hittingHedge calculatorLock in a profit on a futures bet or a live parlayExpected valueIs a price better than the fair one, and by how muchTeaser calculatorTeased lines, the payout, and what each leg must coverRound robinEvery parlay from the same legs, and what one loss leavesOdds comparisonEvery game at every book, best price underlined
Best Bets · Thursday mornings
The three widest gaps on the weekend card, in your inbox by 10.

Plus how the numbers moved since they opened, and which books held the best price. Free.

The Kelly rule stakes a share of the bankroll equal to the edge divided by the odds. Most bettors use a quarter of it, because the chance going in is an estimate. 21+, where legal. Gambling problem? Call 1-800-GAMBLER.