Matched betting calculator

Free

Lay stake, liability and locked profit for qualifying bets and free bets.

Matched betting calculator widget

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index.html

<div data-or-widget="standard"
     data-or-theme="midnight"
     data-or-font="host"></div>
<script src="https://oddsrelay.io/widgets/v1/oddsrelay-widgets.js" crossorigin="anonymous" async></script>

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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.
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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…

Back at the bookmaker, lay at the exchange, and lock the same result whichever way the bet lands. This calculator does the arithmetic for qualifying bets and for both kinds of free bet (stake-not-returned and stake-returned), so you always know the lay stake to place and exactly what you stand to keep.

What it does

Lay stake, liability and the result whether the back bet wins or loses
Qualifying bets plus SNR and SR free bets, with the free-bet retention %
Underlay / overlay and penny, 10p or whole-pound rounding for real exchange stakes
A per-outcome profit breakdown, and one tap to copy the lay stake

How to use it

1Enter your back bet. Type the back stake (or free-bet value) and the bookmaker's back odds.
2Enter the lay side. Add the exchange lay odds and your commission rate.
3Read off the lay stake. The calculator shows the lay stake, liability and the locked result instantly.

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 is the lay stake calculated?

The lay stake balances both outcomes so your result is the same whether the back bet wins or loses. For a qualifying bet it is (back odds × back stake) ÷ (lay odds − commission); a stake-not-returned free bet uses (back odds − 1) in place of back odds.

What is liability?

Liability is the amount the exchange holds when you place a lay bet: the lay stake multiplied by (lay odds − 1). It is what you would lose at the exchange if the back bet wins.

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

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