← Back to Glossary

TRADING GLOSSARY

Lot size: understanding position sizes in forex

In forex trading, positions are measured in lots. A lot defines the number of currency units you are trading. Choosing the correct lot size is critical for managing your risk properly.

Types of lots

Standard lot: 100,000 units of the base currency. Each pip movement is worth approximately $10 (for USD-denominated pairs). Mini lot: 10,000 units. Each pip is worth approximately $1. Micro lot: 1,000 units. Each pip is worth approximately $0.10. Nano lot: 100 units. Each pip is worth approximately $0.01.

Choosing the right lot size

Your lot size should be determined by your account size and risk tolerance. The formula: Lot Size = (Account Balance × Risk Percentage) / (Stop Loss in Pips × Pip Value). For example, with a $10,000 account, 1% risk ($100), and a 50-pip stop loss: Lot Size = $100 / (50 × $10) = 0.2 standard lots (or 2 mini lots).

Common mistakes

Trading standard lots with a small account — a 100-pip move against you on a standard lot is $1,000, which could be 10% or more of a small account. Using the same lot size regardless of stop loss distance — wider stops require smaller positions to maintain the same risk. Not adjusting lot size after losses — a losing streak reduces your account, so the same lot size now represents a larger percentage risk.

AskTrade’s free position size calculator and research reports help you determine the optimal lot size for any trade.

Disclaimer: This is for educational purposes only and does not constitute financial advice. Trading involves significant risk of loss.