{"id":13278,"date":"2026-04-20T12:11:13","date_gmt":"2026-04-20T11:11:13","guid":{"rendered":"https:\/\/duelbits.com/blog\/?p=13278"},"modified":"2026-04-20T12:11:32","modified_gmt":"2026-04-20T11:11:32","slug":"what-is-kelly-criterion-betting-strategy","status":"publish","type":"post","link":"https:\/\/duelbits.com/blog\/guide\/what-is-kelly-criterion-betting-strategy\/","title":{"rendered":"What Is the Kelly Criterion? Formula, Strategy &amp; Betting Guide"},"content":{"rendered":"\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"HowTo\",\n  \"name\": \"How to Apply the Kelly Criterion to a Sports Bet\",\n  \"description\": \"Step-by-step guide to calculating the correct stake size using the Kelly Criterion formula for sports betting bankroll management.\",\n  \"step\": [\n    {\n      \"@type\": \"HowToStep\",\n      \"name\": \"Estimate your true probability of winning\",\n      \"text\": \"Before applying the Kelly formula, you must estimate the true probability that your bet wins. This is the most important and most difficult step. If the sportsbook offers odds implying a 52% chance, but your analysis suggests 57%, that 5% difference is your edge. Be conservative \u2014 overestimating your edge is the most common mistake Kelly bettors make.\"\n    },\n    {\n      \"@type\": \"HowToStep\",\n      \"name\": \"Convert the odds to decimal format\",\n      \"text\": \"Kelly works most cleanly with decimal odds. If you are using fractional or American odds, convert them first. For example, odds of 2.10 in decimal = b of 1.10 (the net profit on a 1-unit win). The b value in the Kelly formula is always decimal odds minus 1.\"\n    },\n    {\n      \"@type\": \"HowToStep\",\n      \"name\": \"Apply the Kelly formula: f = (bp - q) \/ b\",\n      \"text\": \"The Kelly formula is: f = (bp - q) \/ b, where f is the fraction of your bankroll to bet, b is decimal odds minus 1, p is your estimated probability of winning, and q is the probability of losing (1 - p). Example: odds of 2.10 (b = 1.10), you estimate 57% chance of winning (p = 0.57, q = 0.43). f = (1.10 \u00d7 0.57 - 0.43) \/ 1.10 = (0.627 - 0.43) \/ 1.10 = 0.197 \/ 1.10 = 0.179. Kelly recommends betting 17.9% of your bankroll.\"\n    },\n    {\n      \"@type\": \"HowToStep\",\n      \"name\": \"Apply a fractional Kelly multiplier\",\n      \"text\": \"Most experienced bettors do not bet the full Kelly amount. Instead, they use a fractional Kelly \u2014 typically half Kelly (50%) or quarter Kelly (25%). In the example above, half Kelly would be 17.9% \u00d7 0.5 = 8.95% of bankroll. This reduces volatility and protects against edge estimation errors.\"\n    },\n    {\n      \"@type\": \"HowToStep\",\n      \"name\": \"Check the result \u2014 if negative, do not bet\",\n      \"text\": \"If the Kelly formula returns a zero or negative number, the formula is telling you there is no edge and you should not place the bet. A negative result means the implied probability in the odds is higher than your estimated win probability \u2014 the bet has negative expected value.\"\n    },\n    {\n      \"@type\": \"HowToStep\",\n      \"name\": \"Calculate your stake in currency and place the bet\",\n      \"text\": \"Multiply the Kelly fraction by your total bankroll to get the stake amount. If your bankroll is $1,000 and Kelly recommends 8.95% (half Kelly), your stake is $89.50. Place your bet on Duelbits Sportsbook for the applicable market.\"\n    }\n  ]\n}\n<\/script>\n\n\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the Kelly Criterion?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The Kelly Criterion is a mathematical formula for calculating the optimal fraction of your bankroll to bet on any given wager, based on your estimated edge over the odds being offered. Developed by John L. Kelly Jr. in 1956, it is designed to maximise the long-term growth rate of a bankroll while minimising the risk of ruin. It is widely used by professional sports bettors and investors.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the Kelly Criterion formula?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The Kelly Criterion formula is: f = (bp - q) \/ b. Where f is the fraction of your bankroll to stake; b is the decimal odds minus 1 (your net profit on a 1-unit stake); p is your estimated probability of winning; and q is the probability of losing (1 - p). The result gives you the percentage of your bankroll you should bet to maximise long-term growth.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is fractional Kelly betting?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Fractional Kelly is when you bet a fixed fraction of the full Kelly recommendation \u2014 typically half Kelly (50%) or quarter Kelly (25%). Because full Kelly betting produces large swings in bankroll value and is sensitive to errors in probability estimation, most professional bettors use fractional Kelly to reduce variance while still following a mathematically sound staking system.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What does a negative Kelly result mean?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"A negative Kelly result means the formula has determined there is no positive edge in the bet \u2014 your estimated win probability is lower than the probability implied by the odds. When Kelly returns zero or a negative number, the formula recommends not betting at all. The bet has negative expected value.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the biggest risk of using the Kelly Criterion?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The biggest risk is overestimating your edge. The Kelly formula is only as accurate as the probability estimate you feed into it. If your true win probability is lower than you estimated, Kelly will recommend too large a stake, leading to overbetting and potential significant bankroll loss. This is why most bettors use fractional Kelly \u2014 it provides a buffer against estimation errors.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Is the Kelly Criterion the same as flat betting?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"No. Flat betting means staking the same fixed amount or percentage on every bet regardless of your edge. Kelly betting varies the stake size based on the size of the edge \u2014 larger edge means larger stake, smaller edge means smaller stake. Kelly also adjusts automatically as your bankroll grows or shrinks, since the recommended stake is always a fraction of current bankroll.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Who invented the Kelly Criterion?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The Kelly Criterion was developed by John L. Kelly Jr., a researcher at Bell Labs, in 1956. The formula was originally designed to address long-distance telephone signal noise issues. It was later adopted by gamblers and investors as an optimal bet-sizing and capital allocation strategy. Famous investors including Warren Buffett have been associated with Kelly-style thinking.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I use the Kelly Criterion on every bet?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"You can apply the Kelly formula to any bet, but it requires an honest and accurate estimate of your true win probability. Without a genuine edge \u2014 a situation where your probability estimate is higher than the implied probability in the odds \u2014 Kelly will return zero or a negative result and recommend not betting. The formula is most useful for experienced bettors who systematically handicap events and can identify value.\"\n      }\n    }\n  ]\n}\n<\/script>\n\n\n\n<p class=\"wp-block-paragraph\">Most sports bettors focus entirely on which team to back. Far fewer think carefully about how much to stake, and that's where the majority of bankroll damage happens. Bet too little and you leave value on the table. Bet too much and a bad run wipes you out before the edge pays off.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The Kelly Criterion solves this problem. It's a mathematical formula that calculates the precise fraction of your bankroll you should bet on any wager, based on your estimated edge over the odds. This guide explains what it is, how the formula works, how to apply it to sports betting on <a href=\"https:\/\/duelbits.com\/en\">Duelbits<\/a>, and why most professionals use a modified version.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-what-is-the-kelly-criterion\">What Is the Kelly Criterion?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In probability theory, the Kelly Criterion is a formula for risk allocation, sizing a sequence of bets by maximising the long-term expected value of the logarithm of wealth, which is equivalent to maximising the long-term expected geometric growth rate. John Larry Kelly Jr., a researcher at Bell Labs, described the criterion in 1956.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The formula was originally purposed to help Kelly's company reduce long-distance telephone signal noise issues. In time, however, sports bettors and Wall Street traders realised the value of the formula as an investment management system that could help protect assets and maximise earnings. The Kelly Criterion is now widely recognised as the most mathematically optimal sports betting bankroll management strategy.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In practical terms: Kelly tells you how much of your bankroll to bet when you believe you have an edge. The bigger the edge, the bigger the recommended stake. When there is no edge, Kelly recommends betting nothing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The Kelly Criterion is a mathematical formula for determining the optimal stake amount that provides sports bettors with a way of maximising the growth rate of their bankroll over time while minimising losses. Instead of treating every dollar in your bankroll equally, the Kelly Criterion values growth in proportion to your current bankroll.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-the-kelly-criterion-formula\">The Kelly Criterion Formula<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The Kelly formula is:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>f = (bp \u2212 q) \/ b<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Where:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>f<\/strong> = the fraction of your bankroll to bet <strong>b<\/strong> = decimal odds minus 1 (your net profit on a 1-unit win) <strong>p<\/strong> = your estimated probability of winning (expressed as a decimal) <strong>q<\/strong> = your estimated probability of losing (= 1 \u2212 p)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For example, with a 55% win probability and decimal odds of 2.10 (b = 1.10): f = (1.10 \u00d7 0.55 \u2212 0.45) \/ 1.10 = 0.0136 or 1.36% of bankroll.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-a-step-by-step-example\">A Step-by-Step Example<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>The situation:<\/strong> You're betting on a football match. The sportsbook has priced Team A at <strong>2.10<\/strong> decimal odds. After your own analysis, you believe Team A has a <strong>57%<\/strong> chance of winning, higher than the 47.6% implied by the odds. You've identified a positive expected value bet.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Inputs:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>b = 2.10 \u2212 1 = <strong>1.10<\/strong><\/li>\n\n\n\n<li>p = <strong>0.57<\/strong><\/li>\n\n\n\n<li>q = 1 \u2212 0.57 = <strong>0.43<\/strong><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Calculation:<\/strong> f = (1.10 \u00d7 0.57 \u2212 0.43) \/ 1.10 f = (0.627 \u2212 0.43) \/ 1.10 f = 0.197 \/ 1.10 f = <strong>0.179 = 17.9%<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Kelly recommends staking <strong>17.9% of your bankroll<\/strong> on this bet.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If your bankroll is $1,000, that's a $179 stake. If your edge estimate is correct and you make many similar bets over time, Kelly's formula maximises your long-term bankroll growth rate.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-what-if-kelly-returns-a-negative-number\">What If Kelly Returns a Negative Number?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If the Kelly percentage results in less than 0%, the Kelly Criterion recommends walking away and not betting at all, the odds do not seem to be in your favour based on the formula and mathematical calculation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A negative result means your estimated win probability is lower than the probability implied by the odds. The bet has negative expected value. Kelly is not just a staking system, it also functions as a filter, telling you when a bet is worth placing at all.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is one of the Kelly Criterion's most valuable properties for sports bettors: it stops you from betting on games where you don't have a genuine edge.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-what-is-fractional-kelly-betting\">What Is Fractional Kelly Betting?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Full Kelly betting, staking exactly what the formula recommends, is mathematically optimal, but it produces significant bankroll swings in practice. A Kelly bettor has a 1\/3 chance of halving their bankroll before doubling it. A half-Kelly bettor only has a 1\/9 chance of halving their bankroll before doubling it.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Even Kelly supporters usually argue for fractional Kelly, betting a fixed fraction of the amount recommended by Kelly, for a variety of practical reasons, such as wishing to reduce volatility, or protecting against non-deterministic errors in their edge calculations.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The most common approaches:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Half Kelly (0.5\u00d7):<\/strong> Bet 50% of the full Kelly recommendation. Significantly reduces volatility while retaining most of the long-term growth advantage. Most commonly used by professional bettors.<\/li>\n\n\n\n<li><strong>Quarter Kelly (0.25\u00d7):<\/strong> A more conservative approach. Very low variance. Suitable for bettors who have less confidence in the precision of their probability estimates.<\/li>\n\n\n\n<li><strong>Full Kelly (1.0\u00d7):<\/strong> Mathematically optimal but emotionally challenging. Large recommended stakes when you believe you have a big edge. Rarely used even by professionals.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">In the example above, half Kelly would recommend <strong>8.95%<\/strong> ($89.50 on a $1,000 bankroll) instead of the full 17.9%.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-kelly-criterion-vs-other-staking-methods\">Kelly Criterion vs Other Staking Methods<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Staking Method<\/th><th>Stake Size<\/th><th>Adapts to Edge?<\/th><th>Adapts to Bankroll?<\/th><th>Ruin Risk<\/th><\/tr><\/thead><tbody><tr><td>Flat betting (fixed %)<\/td><td>Fixed<\/td><td>No<\/td><td>No<\/td><td>Low<\/td><\/tr><tr><td>Fixed units<\/td><td>Fixed<\/td><td>No<\/td><td>No<\/td><td>Low-Medium<\/td><\/tr><tr><td>Martingale<\/td><td>Doubles after loss<\/td><td>No<\/td><td>No<\/td><td>Very High<\/td><\/tr><tr><td>Kelly Criterion<\/td><td>Variable<\/td><td>Yes<\/td><td>Yes<\/td><td>Low (if correct)<\/td><\/tr><tr><td>Fractional Kelly<\/td><td>Variable (reduced)<\/td><td>Yes<\/td><td>Yes<\/td><td>Very Low<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The Kelly Criterion is considered one of the most effective money management strategies for many types of gamblers, including sports bettors. It offers an excellent way to avoid the common trap of betting too much and blowing your bankroll.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Unlike flat betting, Kelly automatically scales your stakes up as your bankroll grows and down when it shrinks. This compounding mechanic is what makes it mathematically superior over a long betting career.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-the-most-important-rule-accurate-probability-estimation\">The Most Important Rule: Accurate Probability Estimation<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">To apply the Kelly Criterion strategy, bettors must accurately assess the probability of their bet winning. This requires thorough analysis and a deep understanding of the sport and factors affecting the outcome. It's crucial to note that overestimating your edge can lead to overbetting and potential bankroll depletion.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The Kelly formula is only as good as the probability estimate you feed into it. If you estimate 57% and the true probability is 52%, Kelly will recommend a stake size that is too large, and over many bets, this leads to worse outcomes than more conservative staking.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Most professionals use fractional Kelly (25% or less) to account for estimation errors and reduce variance. Think of the fractional multiplier as a built-in safety margin for the inevitable imprecision in your probability estimates.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-when-should-you-use-the-kelly-criterion\">When Should You Use the Kelly Criterion?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Kelly is most appropriate for bettors who:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Have a systematic edge identification process<\/strong>: If you genuinely model events, track line movement, or have access to sharper information than the market, Kelly helps you size those edges correctly. If you're betting on intuition, the formula can't help.<\/li>\n\n\n\n<li><strong>Bet long series of repeated events: <\/strong>Kelly's optimality is proven over long sequences. A single bet is too short a timeframe for Kelly's mathematical properties to manifest.<\/li>\n\n\n\n<li><strong>Can estimate win probabilities honestly<\/strong>: This requires discipline. It means walking away from bets where you can't produce a credible probability estimate, even if you like the team.<\/li>\n\n\n\n<li><strong>Have a sufficient bankroll to absorb variance<\/strong>: The Kelly Criterion is not a fast track to a wagering pot of gold. It's designed to be used as a tool to manage risk and represents just one arrow in the quiver of sports betting bankroll management.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-common-mistakes-when-using-kelly\">Common Mistakes When Using Kelly<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>1. Overestimating your edge.<\/strong> The single most damaging error. If you believe you have 60% probability when the true figure is 52%, Kelly will systematically oversize your stakes and erode your bankroll.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>2. Using full Kelly without understanding the volatility.<\/strong> Full Kelly swings are severe. A losing run can feel catastrophic even when the long-term expectation is positive. Most bettors cannot handle this emotionally.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>3. Applying Kelly to every bet without discrimination.<\/strong> Kelly is a filter as much as a staking formula. If it returns zero or negative, that's the formula telling you not to bet, not a signal to switch to flat betting as a workaround.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>4. Ignoring the effect of the vig.<\/strong> Sportsbook margin means that implied probabilities across a market add up to more than 100%. Always calculate Kelly based on the true probability you estimate, not the implied probability from the odds.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-kelly-criterion-in-practice-on-duelbits\">Kelly Criterion in Practice on Duelbits<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Here's how to apply Kelly to a real bet on <a href=\"https:\/\/duelbits.com\/en\/sportsbook\">Duelbits Sportsbook<\/a>:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">You see a tennis match priced at <strong>2.25<\/strong> (implied probability 44.4%) for the underdog. Your analysis, based on surface stats, head-to-head record, and fitness information, gives the underdog a <strong>50%<\/strong> chance. That's a genuine edge.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Kelly calculation:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>b = 2.25 \u2212 1 = 1.25<\/li>\n\n\n\n<li>p = 0.50<\/li>\n\n\n\n<li>q = 0.50<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">f = (1.25 \u00d7 0.50 \u2212 0.50) \/ 1.25 f = (0.625 \u2212 0.50) \/ 1.25 f = 0.125 \/ 1.25 f = <strong>0.10 = 10%<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">At half Kelly: <strong>5% of your bankroll.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">On a $500 bankroll, that's a <strong>$25 stake<\/strong>, a disciplined, calibrated bet that reflects both your confidence level and the size of your edge.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-frequently-asked-questions\">Frequently Asked Questions<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>What is the Kelly Criterion?<\/strong> The Kelly Criterion is a mathematical formula that calculates the optimal fraction of your bankroll to stake on a bet, based on your estimated edge over the odds. Developed in 1956, it maximises long-term bankroll growth while minimising ruin risk.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>What is the Kelly Criterion formula?<\/strong> f = (bp \u2212 q) \/ b. Where f = fraction of bankroll to bet; b = decimal odds minus 1; p = estimated win probability; q = estimated loss probability (1 \u2212 p).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>What is fractional Kelly betting?<\/strong> Staking a fixed fraction (typically 50% or 25%) of the full Kelly recommendation, to reduce bankroll volatility and protect against probability estimation errors. The most commonly used approach by professional bettors.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>What does a negative Kelly result mean?<\/strong> No edge, the bet has negative expected value. Kelly recommends not betting at all when the result is zero or negative.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>What is the biggest risk of using the Kelly Criterion?<\/strong> Overestimating your edge. If your probability estimate is too high, Kelly recommends stakes that are too large, leading to overbetting and bankroll damage over time.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Is the Kelly Criterion the same as flat betting?<\/strong> No. Flat betting uses a fixed stake on every bet regardless of edge size. Kelly varies the stake based on the size of the edge and automatically scales with your bankroll.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Who invented the Kelly Criterion?<\/strong> John L. Kelly Jr., a researcher at Bell Labs, in 1956. Originally developed for telephone signal processing, it was later adopted by gamblers and investors. It is sometimes called \"Fortune's Formula.\"<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Can I use the Kelly Criterion on every bet?<\/strong> You can apply it to any bet, but it requires an honest probability estimate. Without a genuine edge, Kelly returns zero or negative and recommends not betting. It works best for experienced bettors who systematically identify value.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The Kelly Criterion is a mathematical formula that tells you exactly how much of your bankroll to bet on any given wager, based on your estimated edge over the odds.<\/p>\n","protected":false},"author":217840023,"featured_media":13279,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"{title}\n\n{excerpt}\n\n{url}","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"_wpas_customize_per_network":false,"jetpack_post_was_ever_published":false},"categories":[688637526,688637382],"tags":[],"class_list":["post-13278","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-guide","category-sportsbook"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.7 (Yoast SEO v27.8) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>What Is the Kelly Criterion? 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