SYSTEM STATUS: Online WIN: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 5.5 @ +118) TREND: HOT TREND: MLB Spread hitting 79.5% over 30 days SYSTEM: SYSTEM ALPHA: MLB Value is +538.1 units this season TREND: HOT TREND: MLB Value hitting 80.0% over 30 days SYSTEM: SYSTEM ALPHA: MLB Value is +601.4 units this season SYSTEM: SYSTEM ALPHA: MLB Value is +601.4 units this season SYSTEM: SYSTEM ALPHA: MLB Value is +1218.7 units this season TREND: HOT TREND: MLB Value hitting 79.6% over 30 days WIN: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 4 @ +400) WIN: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 5 @ +195) TREND: HOT TREND: MLB Totals hitting 80.0% over 30 days WIN: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 5.5 @ +106) WIN: WON: Cincinnati Reds @ Milwaukee Brewers (Milwaukee Brewers -1.5 @ +126) SYSTEM: SYSTEM ALPHA: MLB Value is +1238.5 units this season WIN: WON: Cincinnati Reds @ Milwaukee Brewers (Milwaukee Brewers -1.5 @ +124) WIN: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 3 @ +750) WIN: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 4.5 @ +240) WIN: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 3.5 @ +450) TREND: HOT TREND: MLB Spread hitting 79.5% over 30 days WIN: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 2.5 @ +750) RESULT: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 5.5 @ +118) 0.0% EDGE: HOT TREND: MLB Spread hitting 79.5% over 30 days 0.0% EDGE: SYSTEM ALPHA: MLB Value is +538.1 units this season 0.0% EDGE: HOT TREND: MLB Value hitting 80.0% over 30 days 0.0% EDGE: SYSTEM ALPHA: MLB Value is +601.4 units this season 0.0% EDGE: SYSTEM ALPHA: MLB Value is +601.4 units this season 0.0% EDGE: SYSTEM ALPHA: MLB Value is +1218.7 units this season 0.0% EDGE: HOT TREND: MLB Value hitting 79.6% over 30 days RESULT: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 4 @ +400) RESULT: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 5 @ +195) 0.0% EDGE: HOT TREND: MLB Totals hitting 80.0% over 30 days RESULT: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 5.5 @ +106) RESULT: WON: Cincinnati Reds @ Milwaukee Brewers (Milwaukee Brewers -1.5 @ +126) 0.0% EDGE: SYSTEM ALPHA: MLB Value is +1238.5 units this season RESULT: WON: Cincinnati Reds @ Milwaukee Brewers (Milwaukee Brewers -1.5 @ +124) RESULT: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 3 @ +750) RESULT: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 4.5 @ +240) RESULT: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 3.5 @ +450) 0.0% EDGE: HOT TREND: MLB Spread hitting 79.5% over 30 days RESULT: WON: San Francisco Giants @ Arizona Diamondbacks (San Francisco Giants 2.5 @ +750)
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Free staking tool

Stake the exact amount your edge is worth

The Kelly Criterion sizes every bet for maximum long-term growth. Enter your bankroll, the odds and your win probability — get the optimal stake instantly, then dial it to half or quarter Kelly to tame variance.

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Recommended stake
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% of bankroll
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Full Kelly %
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Your edge
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Kelly fraction = (b·p − q) ÷ b, where b = decimal odds − 1. A negative result means no edge — don't bet.

See our verified results — every pick settled and recorded

We size every pick with Kelly for you

Each model pick already carries its calibrated probability and a suggested stake — no maths required. See tonight's sized plays, free.

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How to use it

  1. Enter the bankroll you're betting with.
  2. Set your honest win probability — your real edge, not hope.
  3. Add the odds in decimal, American or fractional.
  4. Choose half or quarter Kelly to soften the swings.

Worked example

Bankroll$1,000
Win prob55%
Odds2.00
Full Kelly10.0%
Half-Kelly stake$50.00

Kelly — quick answers

What is the Kelly Criterion?

A formula that sizes bets to maximise long-term bankroll growth: fraction = (b·p − q) ÷ b.

Full, half or quarter Kelly?

Most pros use half or quarter Kelly — far less volatile and far more forgiving if your probability estimate is slightly off.

What happens if I have no edge?

If the formula returns zero or negative, the price doesn't beat your probability. The optimal stake is nothing — don't bet.

Bet Better is not a bookmaker and does not accept wagers. Tools are for information only. Gamble responsibly — never stake more than you can afford to lose.