What does 'bonus retention' mean?

It is the share of the bonus you expect to convert to cash after laying it off, entered as a percentage. The bonus value used in the maths is the max bonus multiplied by that retention rate.

What is the difference between win and loss mode?

Win mode is for offers that pay the bonus when your back bet wins; loss mode is for money-back-if-it-loses offers. Each changes the lay stake and which outcome the bonus value lands in.

What do Standard, Underlay and Overlay do?

They are three ways to size the lay: Standard balances the two outcomes, Underlay minimises the worst outcome, and Overlay maximises the best. The profit legs use the same maths; only the lay stake differs.

Bonus bet calculator

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Lay a bonus offer and see the qualifying loss and profit, on a win or a loss.

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Some bookmaker offers pay a bonus when your bet wins; others pay it when the bet loses (money back). Back at the bookmaker and lay at the exchange, and this calculator sizes the lay so the bonus value is captured. Set the max bonus and the share you expect to turn into cash, pick win or loss mode and a Standard, Underlay or Overlay lay, and it shows the lay stake, the worst-case qualifying loss and the potential profit.

What it does

Bonus paid on a win or on a loss (money-back), each with its own lay maths
Standard, Underlay or Overlay lay methods
Qualifying bets and free (stake-not-returned) bets
Back/lay rating, lay stake, qualifying loss and potential profit, one tap to copy the lay stake
Runs entirely in your browser: no account, nothing leaves the page

How to use it

1Enter the bet. Type the back stake, back odds, lay odds and exchange commission.
2Add the bonus terms. Enter the max bonus and the retention % you expect, then pick whether it pays on a win or a loss.
3Read the lay. The calculator shows the lay stake, qualifying loss and potential profit, with one tap to copy the lay stake.

What powers this

This calculator runs entirely in your browser. There's no account, no API key and no 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

What does 'bonus retention' mean?: It is the share of the bonus you expect to convert to cash after laying it off, entered as a percentage. The bonus value used in the maths is the max bonus multiplied by that retention rate.
What is the difference between win and loss mode?: Win mode is for offers that pay the bonus when your back bet wins; loss mode is for money-back-if-it-loses offers. Each changes the lay stake and which outcome the bonus value lands in.
What do Standard, Underlay and Overlay do?: They are three ways to size the lay: Standard balances the two outcomes, Underlay minimises the worst outcome, and Overlay maximises the best. The profit legs use the same maths; only the lay stake differs.

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

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