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OddsRelay

Odds converter

Free

Decimal, fractional, American and implied probability, instantly.

Odds converter widget

Design: font, colours, radius
Font

Inherit the font of the page it sits on.

Colours
Radius

Default keeps the widget's own corners.

Accent, surface, text and radius are the only overridable tokens: a bounded set that keeps every widget readable. Fonts are stacks, so an embed never downloads one.

Embed code
Embed codeLive

This rewrites itself as you change the controls above: font, colours and radius. Copy it from the button under the code.

index.html
<div data-or-widget="odds-converter"
     data-or-theme="midnight"
     data-or-font="host"></div>
<script src="https://oddsrelay.io/widgets/v1/oddsrelay-widgets.js" crossorigin="anonymous" async></script>
Copy this and paste it on your site.

Paste it once, anywhere. The script auto-mounts every data-or-widget element and is style-isolated in a Shadow DOM, so it never clashes with your CSS.

Installing on WordPress, Webflow, Squarespace, Wix or React?
WordPress
Add a Custom HTML block (or switch the classic editor to the Text tab) and paste the snippet.
Webflow
Drop in an Embed element, paste the snippet, and publish. The widget renders on the published site.
Squarespace
Insert a Code block where you want the widget and paste the snippet as HTML.
Wix
Add an Embed HTML element (iFrame-free custom code) and paste the snippet.
Shopify
Paste into a Custom Liquid section (or theme.liquid for every page). A section keeps the widget on the one template you want it on.
React / Next.js
Render the div, then load the script once (e.g. next/script or an effect). The bundle auto-mounts new [data-or-widget] elements; call window.OddsRelay.scan() after client-side navigations if needed.

Loading the interactive widget…

Different books, different formats. Type a price in any format (decimal, fractional, American or a probability) and see all of them at once, including the implied probability the price bakes in.

What it does

  • Decimal ⇄ fractional ⇄ American ⇄ implied probability
  • Clean betting fractions (1.91 → 10/11)
  • Implied probability for any price
  • Accepts fractional input like 11/4

How to use it

  1. 1Pick the input format. Choose decimal, fractional, American or probability.
  2. 2Type the value. Enter the odds, e.g. 2.5, 11/4, +150 or 40.
  3. 3See every format. The converter shows all formats plus the implied probability, each one tap to copy.

What powers this

This calculator runs entirely in your browser. It needs no account, key or feed, and nothing you type leaves the page. The maths is the same commodity matched-betting and value arithmetic used across the industry, implemented carefully and unit-tested.

Questions

How do you convert decimal odds to a probability?

Implied probability is 1 ÷ decimal odds. So 2.0 implies 50%, 4.0 implies 25%, and so on (before any bookmaker margin).

Why is 1.91 shown as 10/11 and not 91/100?

We approximate to the clean betting fraction punters use, rather than the literal decimal fraction. 10/11 is the recognised price, and the exact decimal is still shown alongside it.

How do American odds work?

Positive American odds show the profit on a 100 stake (+150 → 2.5 decimal). Negative odds show the stake needed to win 100 (−200 → 1.5 decimal).

18+ · Data product for licensed operators. Please gamble responsibly.

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