\documentclass[10pt,a4paper]{article} % Packages \usepackage{fancyhdr} % For header and footer \usepackage{multicol} % Allows multicols in tables \usepackage{tabularx} % Intelligent column widths \usepackage{tabulary} % Used in header and footer \usepackage{hhline} % Border under tables \usepackage{graphicx} % For images \usepackage{xcolor} % For hex colours %\usepackage[utf8x]{inputenc} % For unicode character support \usepackage[T1]{fontenc} % Without this we get weird character replacements \usepackage{colortbl} % For coloured tables \usepackage{setspace} % For line height \usepackage{lastpage} % Needed for total page number \usepackage{seqsplit} % Splits long words. %\usepackage{opensans} % Can't make this work so far. Shame. Would be lovely. \usepackage[normalem]{ulem} % For underlining links % Most of the following are not required for the majority % of cheat sheets but are needed for some symbol support. \usepackage{amsmath} % Symbols \usepackage{MnSymbol} % Symbols \usepackage{wasysym} % Symbols %\usepackage[english,german,french,spanish,italian]{babel} % Languages % Document Info \author{BetBetter} \pdfinfo{ /Title (betting-odds-and-implied-probability.pdf) /Creator (Cheatography) /Author (BetBetter) /Subject (Betting Odds and Implied Probability Cheat Sheet) } % Lengths and widths \addtolength{\textwidth}{6cm} \addtolength{\textheight}{-1cm} \addtolength{\hoffset}{-3cm} \addtolength{\voffset}{-2cm} \setlength{\tabcolsep}{0.2cm} % Space between columns \setlength{\headsep}{-12pt} % Reduce space between header and content \setlength{\headheight}{85pt} % If less, LaTeX automatically increases it \renewcommand{\footrulewidth}{0pt} % Remove footer line \renewcommand{\headrulewidth}{0pt} % Remove header line \renewcommand{\seqinsert}{\ifmmode\allowbreak\else\-\fi} % Hyphens in seqsplit % This two commands together give roughly % the right line height in the tables \renewcommand{\arraystretch}{1.3} \onehalfspacing % Commands \newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour \newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols \newcolumntype{x}[1]{>{\raggedright}p{#1}} % New column types for ragged-right paragraph columns \newcommand{\tn}{\tabularnewline} % Required as custom column type in use % Font and Colours \definecolor{HeadBackground}{HTML}{333333} \definecolor{FootBackground}{HTML}{666666} \definecolor{TextColor}{HTML}{333333} \definecolor{DarkBackground}{HTML}{1F5FBF} \definecolor{LightBackground}{HTML}{F1F5FB} \renewcommand{\familydefault}{\sfdefault} \color{TextColor} % Header and Footer \pagestyle{fancy} \fancyhead{} % Set header to blank \fancyfoot{} % Set footer to blank \fancyhead[L]{ \noindent \begin{multicols}{3} \begin{tabulary}{5.8cm}{C} \SetRowColor{DarkBackground} \vspace{-7pt} {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}} } \end{tabulary} \columnbreak \begin{tabulary}{11cm}{L} \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Betting Odds and Implied Probability Cheat Sheet}}}} \\ \normalsize{by \textcolor{DarkBackground}{BetBetter} via \textcolor{DarkBackground}{\uline{cheatography.com/219378/cs/48582/}}} \end{tabulary} \end{multicols}} \fancyfoot[L]{ \footnotesize \noindent \begin{multicols}{3} \begin{tabulary}{5.8cm}{LL} \SetRowColor{FootBackground} \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}} \\ \vspace{-2pt}BetBetter \\ \uline{cheatography.com/betbetter} \\ \end{tabulary} \vfill \columnbreak \begin{tabulary}{5.8cm}{L} \SetRowColor{FootBackground} \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}} \\ \vspace{-2pt}Published 8th November, 2026.\\ Updated 8th November, 2026.\\ Page {\thepage} of \pageref{LastPage}. \end{tabulary} \vfill \columnbreak \begin{tabulary}{5.8cm}{L} \SetRowColor{FootBackground} \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}} \\ \SetRowColor{white} \vspace{-5pt} %\includegraphics[width=48px,height=48px]{dave.jpeg} Measure your website readability!\\ www.readability-score.com \end{tabulary} \end{multicols}} \begin{document} \raggedright \raggedcolumns % Set font size to small. Switch to any value % from this page to resize cheat sheet text: % www.emerson.emory.edu/services/latex/latex_169.html \footnotesize % Small font. \begin{multicols*}{3} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{One price, three formats}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{{\bf{Decimal 2.50}} = stake back x 2.50 (a \$10 bet returns \$25, profit \$15) \newline % Row Count 2 (+ 2) {\bf{Fractional 3/2}} = profit 3 for every 2 staked (same as 2.50) \newline % Row Count 4 (+ 2) {\bf{American +150}} = profit \$150 on a \$100 bet (same as 2.50) \newline % Row Count 6 (+ 2) {\bf{American -200}} = stake \$200 to win \$100 (decimal 1.50) \newline % Row Count 8 (+ 2) Convert: \newline % Row Count 9 (+ 1) Decimal = 1 + fraction (3/2 -\textgreater{} 2.50) \newline % Row Count 10 (+ 1) Decimal from +A = 1 + A/100 \newline % Row Count 11 (+ 1) Decimal from -A = 1 + 100/A \newline % Row Count 12 (+ 1) +A from decimal d \textgreater{}= 2: (d - 1) x 100 \newline % Row Count 13 (+ 1) -A from decimal d \textless{} 2: 100 / (d - 1) \newline % Row Count 14 (+ 1) Free converter: \{\{link="https://betbetter.world/tools/odds-converter"\}\}betbetter.world/tools/odds-converter\{\{/link\}\}% Row Count 17 (+ 3) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{All three formats describe the same bet; only the way of writing it changes.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Are the odds right? Checking calibration}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{{\bf{Calibration}} = do events priced at X\% happen about X\% of the time? \newline % Row Count 2 (+ 2) 1. Remove the margin from each closing price \newline % Row Count 3 (+ 1) 2. Group outcomes into bands (50-60\%, 60-70\% ...) \newline % Row Count 4 (+ 1) 3. Compare the average priced chance with the share that won \newline % Row Count 6 (+ 2) 4. Judge gaps against the standard error: sqrt(p x (1-p) / n) \newline % Row Count 8 (+ 2) {\bf{What open data shows:}} across 18,238 settled two-outcome markets (Nov 2024 - Jul 2026, five sports), outcomes landed within about 2 points of the margin-free price in every band. Small gaps like that are often inside sampling error. \newline % Row Count 13 (+ 5) Full dataset (36,476 rows, CC BY 4.0): DOI 10.5281/zenodo.21764674 \newline % Row Count 15 (+ 2) Study: \{\{link="https://betbetter.world/studies/market-calibration"\}\}Do betting odds tell the truth?\{\{/link\}\}% Row Count 18 (+ 3) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Example: p = 0.8, n = 2,000 gives a standard error of about 0.9 points, so a 1.5-point gap is not significant.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Price to chance (implied probability)}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{{\bf{Decimal d:}} chance = 1 / d \newline % Row Count 1 (+ 1) 2.50 -\textgreater{} 1 / 2.50 = 40\% \newline % Row Count 2 (+ 1) 1.50 -\textgreater{} 66.7\% \newline % Row Count 3 (+ 1) {\bf{Fractional a/b:}} chance = b / (a + b) \newline % Row Count 4 (+ 1) 3/2 -\textgreater{} 2 / 5 = 40\% \newline % Row Count 5 (+ 1) {\bf{American +A:}} chance = 100 / (A + 100) \newline % Row Count 6 (+ 1) +150 -\textgreater{} 100 / 250 = 40\% \newline % Row Count 7 (+ 1) {\bf{American -A:}} chance = A / (A + 100) \newline % Row Count 8 (+ 1) -200 -\textgreater{} 200 / 300 = 66.7\% \newline % Row Count 9 (+ 1) Short-cut: an even-money price (2.00, 1/1, +100) means 50\%.% Row Count 11 (+ 2) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{This is the chance the price implies before the bookmaker margin is removed.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Key terms}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{{\bf{Implied probability}}: the chance a price suggests (1 / decimal odds) \newline % Row Count 2 (+ 2) {\bf{Margin / vig / overround}}: how far the implied chances add up above 100\% \newline % Row Count 4 (+ 2) {\bf{Fair (no-vig) odds}}: odds after the margin is removed \newline % Row Count 6 (+ 2) {\bf{Closing price}}: the last price before the event starts \newline % Row Count 8 (+ 2) {\bf{Favourite-longshot bias}}: favourites and longshots being priced too short or too long on average \newline % Row Count 10 (+ 2) {\bf{Brier score}}: average squared error of a forecast chance (a coin flip scores 0.25) \newline % Row Count 12 (+ 2) {\bf{Calibration}}: priced chances match how often things happen% Row Count 14 (+ 2) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Odds are forecasts. Knowing how to read them is a statistics skill, not a betting tip.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Removing the margin (the vig)}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Both sides of a two-way market add up to more than 100\%. The extra is the bookmaker's margin. \newline % Row Count 2 (+ 2) {\bf{Example:}} Team A 1.80, Team B 2.10 \newline % Row Count 3 (+ 1) Implied: 1/1.80 = 55.6\%, 1/2.10 = 47.6\% \newline % Row Count 4 (+ 1) Total = 103.2\% -\textgreater{} margin about 3.2\% \newline % Row Count 5 (+ 1) {\bf{Fair chance (simple method):}} divide each by the total \newline % Row Count 7 (+ 2) A = 55.6 / 103.2 = 53.9\% \newline % Row Count 8 (+ 1) B = 47.6 / 103.2 = 46.1\% \newline % Row Count 9 (+ 1) {\bf{Fair odds}} = 1 / fair chance \newline % Row Count 10 (+ 1) A = 1.86, B = 2.17 \newline % Row Count 11 (+ 1) Other methods (Shin, power, odds ratio) spread the margin differently between favourite and longshot.% Row Count 14 (+ 3) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Typical margins, Jul-Sep 2026, 69.6M markets: about 4.8\% on who-wins bets and 7.6\% on player props.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} % That's all folks \end{multicols*} \end{document}