How to Calculate Your Position Size in Different Forex Pairs and Account Currencies

Let’s say you want to buy EUR/GBP and your broker account is denominated in USD.

In this trade, you only want to risk USD $100. But you’re not trading US dollars, you are trading euros and pounds. How do you calculate your position size?

In this lesson, we’ll teach you how to determine your position size if you are trading currency pairs that aren’t in your account denomination.

If your account denomination is not in the currency pair traded, but the same as the conversion pair’s counter currency…

Example: USD account trading EUR/GBP

Ned, who we introduced in the previous lesson, is back in the U.S. Today, he decides to trade EUR/GBP with a 200 pip stop.

To find the correct position size, we need to find the value of Ned’s risk in British Pounds.

Remember, the value of a currency pair is in the counter currency.

Step 1: Determine risk amount in USD

Okay, let’s straighten things out here. He’s back trading with his U.S. broker selling EUR/GBP and he only wants to risk 1% of his USD 5,000 account, or USD 50.

To find the correct forex position size in this situation, we need the GBP/USD exchange rate.

Step 2: Convert USD risk amount to GBP

Let’s use 1.7500 and because his account is in USD, we need to invert that exchange rate to find the proper amount in British Pounds.

USD 50 * (GBP 1/USD 1.7500) = GBP 28.57

Now, we just finish the rest the same way as the other examples.

Step 3: Convert GBP risk amount to pips

Divide by the stop loss in pips:

(GBP 28.57)/(200 pips) = GBP 0.14 per pip

Step 4: Calculate for position size

And finally, multiply by the known unit-to-pip value ratio:

(GBP 0.14 per pip) * [(10k units of EUR/GBP)/(GBP 1 per pip)] = approximately 1,429 units of EUR/GBP

Ned can sell no more than 1,429 units of EUR/GBP to stay within his pre-determined risk levels.

If your account denomination is not in the currency pair traded, but the same as the conversion pair’s base currency…

Example: CHF account trading USD/JPY

Ned decides to go snowboarding in Switzerland, and in between a couple of double black diamond runs, he opens up his trading account on his super spy phone with a local forex broker.

He sees a great setup on USD/JPY, and he has decided that he will get out of the trade if it goes beyond a major resistance level–about 100 pips against him.

Step 1: Determine risk amount in CHF

Ned will only risk the usual 1% of his CHF 5,000 account or CHF 50.

Step 2: Convert CHF risk amount to JPY

First, we need to find the value of CHF 50 in Japanese yen, and since the account is the same denomination as the conversion pair’s base currency, all we have to do is multiply the amount risked by CHF/JPY exchange rate (85.00):

CHF 50 * (JPY 85.00/ CHF 1) = JPY 4,250

Now, we just finish the rest the same way as the other examples.

Step 3: Convert JPY risk amount to pips

Divide by the stop loss in pips:

JPY 4,250/100 pips = JPY 42.50 per pip

Step 4: Calculate for position size

And finally, multiply by a known unit-to-pip value ratio:

JPY 42.50 per pip * [(100 units of USD/JPY)/(JPY 1 per pip)] = approximately 4,250 units of USD/JPY

Shabam! There you have it!

Ned can trade no more than 4,250 units of USD/JPY to keep his loss at CHF 50 or less.

Reprinted from Babypips, the copyright all reserved by the original author.