# Single-Market Dutching Formulae

Dutching is an excellent tool in the hands of an experienced trader. It can increase your chances for winning by spreading your bet evenly across several outcomes. If you happen to hear this term for the first time, here is a short description of how it works.

**Dutching in a Nutshell**

Instead of backing on just one outcome (a player, a horse, a score etc.) to win, you back on many different outcomes at once, expecting to gain profit if at least one of them wins. This may, for example, mean that you back on several horses in a horse race, or on several score outcomes in the Correct Score football market. The Dutching principle allows you to set the target profit you want to win in case one of your chosen selection wins, or limit the total liability of your bets in case none of them wins (but not both at once, see more of this below).

There can be Back Dutching and Lay Dutching. With Back Dutching, you place back bets on the selections (runners, teams etc.) you believe have high chances of winning. With Lay Dutching, you place lay bets on the selections that you reckon will likely lose.

**Automated Dutching in MarketFeeder Pro**

There are two great ways to do Dutching in MarketFeeder Pro: through the built-in Auto-Dutching experience and through triggers that place Dutching bets.

In both cases, the program will do all the math on its own, letting you simply key in your desired profit/liability and enjoy the fully automated bet placement service.

See some Dutching examples in our trigger library.

**Dutching Formulae**

Many sites will offer you a Dutching calculator, and indeed, if you are looking for a quick solution for manual trading, a Dutching calculator is the way to go. However, if you are looking for a more serious approach to it and hoping to do your own bit of bet programming, you will need the “magic formulae.” You will appreciate that this is the only page (and I’ve done my research!) that will offer you these formulae in one place and ready to use.

The basic formulae for Dutching bet amounts are as follows:

**For Backing:**

If you want a target profit of PROFIT, then the amount for each bet is calculated as follows.

Amount = PAYOUT/back_price

Where

- Back_price is the price of the selection you are backing on;
- PAYOUT = PROFIT*100/(100 – back_book);
- Back_book is the sum of the chances to win of all the selections you are backing on, i.e.
**100/back_price1 + 100/back_price2 + … + 100/back_priceN**. For a Back Dutching to be profitable, the back_book MUST be less than 100.

If you want to set the maximum LIABILITY for the bets in case none of them wins, then the amount for each bet is calculated as follows.

Amount = PAYOUT/back_price

Where

PAYOUT = LIABILITY*100/back_book

**For Laying**

If you want a target profit of PROFIT if none of the laid selections wins, then the amount for each bet is calculated as follows.

Amount = PAYOUT/lay_price

Where

- Lay_price is the price of the selection you are laying on;
- PAYOUT = PROFIT*100/lay_book;
- Lay_book is the sum of the chances to win of all the selections you are laying on, i.e.
**100/lay_price1 + 100/lay_price2 + … + 100/lay_priceN**. With Lay Dutching, the requirement for the book value is different compared to Back Dutching. You can lay if lay_book is less than 100: you will end up with potential loss on the selections you laid on and profit on all other selections. However, if you are lucky enough to lay on selections whose compound lay_book is greater than 100, you will secure guaranteed profit on all selections in the market!

If you want to set the maximum LIABILITY for the bets in case one of the laid selection wins, then the amount for each bet is calculated as follows.

Amount = PAYOUT/lay_price

Where

PAYOUT = LIABILITY*100/(100 - lay_book)

As you can see above, the Lay Dutching formulae are just the reverse version of the Back Dutching ones!

Note that you will pay a standard exchange commission (which is 5% on most markets on BetFair) on your profit.

**Formulae for target profit through liability and vice versa**

Here is another set of formulae you will find useful, for example, in situations when you have set a maximum liability for your Back Dutching, but also want to recoup any losses generated in the previous games. In that case, you will need to convert the target profit (the loss you need to recoup) into the maximum liability for your bets.

**For Backing:**

LIABILITY = back_book*(PROFIT/(100 - back_book))

PROFIT = (LIABILITY/back_book)*(100 - back_book)

**For Laying:**

LIABILITY = (PROFIT/lay_book)*(100 - lay_book)

PROFIT = lay_book*(LIABILITY/(100 - lay_book))

Now it becomes clear why you can set either fixed liability or fixed profit, but not both at the same time – because they are a function of each other.

Note another important thing: with high prices (above 10.0) or small target profit/max liability you are likely to get errors in the resulting P/L due to fractions of pennies dropped when rounding the size of the bet. This is normal and it should not greatly affect your winnings.

The above narrative is true for Dutching in both win and place markets: only with Dutching in place markets, you multiply the book by the number of winning places before putting it into the formulae. Besides, expect to win the target profit only if N selections you bet on are placed (not just one, as is the case in win markets), where N is the number of winning places.

The story is quite different for cross-market Dutching, as that is where commission hits hard and disrupts the standard formulae. Read more on this in Cross-Market Dutching Formulae.