Choosing a Lot Size in Forex Trading

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When you first get your feet wet with forex training, you'll learn about trading lots. In the context of forex trading, a lot refers to a batch of currency the trader controls. The lot size is variable. Typical designations for lot size include standard lots, mini lots, and micro lots. It is important to note that the lot size directly impacts and indicates the amount of risk you're taking.

Lot Size Matters

Finding the lot size that best balances opportunity and risk is a very important individual decision. Using a tool like a risk-management calculator can help you clarify your decisions about lot size, but you should do so by factoring in your own risk tolerance and your trading objectives.

The trading lot size directly impacts how much a market move affects your accounts. For example, a 100-pip move on a small trade will not be felt nearly as much as the same 100-pip move on very large trade size.

That is why it is important to select the proper lot size. A lot size that is too large will make the trade riskier and more uncomfortable to hold on to. A lot size that is too small might not generate enough potential gain to be worthwhile.  

Trading With Micro Lots

Micro lots are the smallest tradeable lot available to most brokers. They are lots of 1,000 units of your account funding currency. If your account is funded in U.S. dollars, this means that a micro lot is $1,000 worth of the base currency you want to trade. If you are trading a dollar-based pair, one pip would be equal to ten cents. Micro lots are very good for beginners who want to keep risk to a minimum while practicing their trading.

Moving up to Mini Lots

Before micro lots, there were mini lots. A mini lot is 10,000 units of your account funding currency. If you are using a dollar-based account and trading a dollar-based pair, each pip in your trade would be worth about $1.00. If you are a beginner and you want to start trading using mini lots, make sure that you're well-capitalized.

While $1.00 per pip seems like a small amount, in forex trading, the market can move 100 pips in a day, sometimes even in an hour. If the market is moving against you, that adds up to a $100 loss. It's up to you to decide your ultimate risk tolerance, but to trade a mini account, you should start with at least $2,000 to be comfortable.

Using Standard Lots

A standard lot is a 100,000-unit lot. That is a $100,000 trade if you are trading in dollars. Trading with this size of position means that the trader's account value will fluctuate by $10 for each one pip move. For a trader who has only $2,000 in their account (usually the minimum required to trade a standard lot), a 20-pip move can make a 10% change in account balance, so most retail traders with small accounts don't trade in standard lots.

Most forex traders you come across are going to be trading mini lots or micro lots. It might not feel glamorous, but keeping your lot size within reason relative to your account size will help you preserve your trading capital to continue trading for the long term.

A Helpful Visualization

In his book Trading In The Zone, trading author Mark Douglas offers a useful analogy between choosing a lot size and walking a precarious bridge or even a tightrope. The idea is that the larger the lot size a trader chooses, the more dramatic and emotional the trading experience is likely to become.

To illustrate this example, a very small trade size relative to your account capital would be like walking over a valley on a very wide, stable bridge where little would disturb you even if there were a storm or heavy rains. Now imagine that the larger the trade you place, the smaller and riskier the support or bridge under you becomes.

When you place an extremely large trade size relative to your account balance, the bridge gets as narrow as a tightrope wire. Any small movement in the market could be like a gust of wind, blowing the trader off balance and leading to disaster.

Frequently Asked Questions (FAQs)

How much money do you need to trade forex?

The forex market is less regulated than other markets, so requirements like minimum account size are typically set by brokerages. You may be able to trade forex with as little as $100, but it's better to save up more and give yourself wiggle room for losses.

How do you calculate forex profit?

The first step in calculating forex profit is to measure the movement of the pair. For instance, you may be trading a dollar-based pair that moves three pips in your favor, or $0.30. Multiply that profit by your lot size and number of lots. If you're trading two standard-size lots, then that would be two lots times 100,000 units per lot times $0.30 profit (2 x 100,000 x 0.3 = $60,000). If you used leverage, you'll need to subtract what you borrowed from that amount to learn how much profit you'll get to pocket.

Article Sources

  1. 7e7. "What Is a Lot in Forex?"

  2. FxPro. "Pip Calculator."

  3. Mark Douglas. "Trading in the Zone." Penguin Random House, 2000.