{"id":38191,"date":"2026-06-22T09:00:00","date_gmt":"2026-06-22T08:00:00","guid":{"rendered":"http:\/\/localhost:8888\/guide\/fair-odds-and-the-vig-free-price\/"},"modified":"2026-06-22T09:00:00","modified_gmt":"2026-06-22T08:00:00","slug":"fair-odds-and-the-vig-free-price","status":"publish","type":"spx_guide","link":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/guide\/fair-odds-and-the-vig-free-price\/","title":{"rendered":"Fair Odds and the Vig-Free Price"},"content":{"rendered":"\n<p class=\"anps-post-betting__lead wp-block-paragraph\">Every market is two things at once: an estimate of probability and a charge for making it. Separating them lets you see the estimate on its own, compare it with your own, and compare it between bookmakers on equal terms. The arithmetic takes a minute.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"simple\">The simple method<\/h2>\n\n\n\n<ol class=\"wp-block-list anps-post-betting__steps\">\n<li><strong>Convert each price.<\/strong> Home 1.91 \u2192 52.36%. Away 1.99 \u2192 50.25%.<\/li>\n\n<li><strong>Add them.<\/strong> 102.61%. The margin is 2.61 points.<\/li>\n\n<li><strong>Divide each by the total.<\/strong> 52.36 \u00f7 102.61 = 51.03%. 50.25 \u00f7 102.61 = 48.97%. They now add to 100.<\/li>\n\n<li><strong>Convert back.<\/strong> 1 \u00f7 0.5103 = 1.96. 1 \u00f7 0.4897 = 2.04. Those are the fair prices.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">The method assumes the margin is spread in proportion to each outcome\u2019s probability. That is approximately true on tight two-way markets at sharp operators, and less true everywhere else.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"breaks\">Where it breaks<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Bookmakers do not apply their margin evenly. Long shots are shaded harder than favourites \u2014 the favourite\u2013longshot bias \u2014 because casual money prefers big prices. On a three-way football market the draw and the away side typically carry more of the margin than the home favourite. Proportional removal therefore slightly understates the favourite\u2019s true probability and overstates the outsider\u2019s.<\/p>\n\n\n\n<div class=\"wp-block-group anps-post-betting__callout is-note is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"anps-post-betting__callout-title wp-block-paragraph\"><strong>A better approximation<\/strong><\/p>\n\n<p class=\"wp-block-paragraph\">Remove the margin in proportion to the odds rather than the probabilities \u2014 the \u201cpower\u201d or \u201cShin\u201d methods in the literature. For everyday use, take the vig-free line from the sharpest operator you can see, which will already have less bias baked in than any correction you apply to a wide one.<\/p>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"use\">What to do with it<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Use the vig-free price from Kestrel or NovaBet \u2014 the two sharpest in our guide \u2014 as the market\u2019s probability, and compare your own estimate with that rather than with any bookmaker\u2019s shaded price. Then find the best price actually available, anywhere, and check it against the same fair line. The gap between those two numbers, in probability points, is your expected edge on the bet; if it is smaller than zero, the market is offering you nothing, however strongly you feel.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Stripping the margin out of a two-way market to see what the bookmaker really thinks.<\/p>\n","protected":false},"author":21,"featured_media":33827,"menu_order":9,"template":"","tags":[240,260,286],"spx_guide_topic":[486],"spx_guide_level":[375],"class_list":["post-38191","spx_guide","type-spx_guide","status-publish","has-post-thumbnail","hentry","tag-margins","tag-odds","tag-probability"],"_links":{"self":[{"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/spx_guide\/38191","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/spx_guide"}],"about":[{"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/types\/spx_guide"}],"author":[{"embeddable":true,"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/users\/21"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/media\/33827"}],"wp:attachment":[{"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/media?parent=38191"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/tags?post=38191"},{"taxonomy":"spx_guide_topic","embeddable":true,"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/spx_guide_topic?post=38191"},{"taxonomy":"spx_guide_level","embeddable":true,"href":"https:\/\/preview.sportpulse.anpsthemes.com\/betting\/wp-json\/wp\/v2\/spx_guide_level?post=38191"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}