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Glossary

Lot Size

Definition

Lot size refers to the number of units of a financial instrument in a trade. In forex, a standard lot is 100,000 units, a mini lot is 10,000, and a micro lot is 1,000. In futures, lot sizes vary by contract.

Understanding lot sizes is fundamental to proper position sizing and risk management. In forex, if you trade 1 standard lot of EUR/USD, each pip movement is worth approximately $10. For a mini lot, it's $1, and for a micro lot, it's $0.10. In futures, lot sizes are defined by the contract — for example, one E-mini S&P 500 contract has a multiplier of $50 per point.

For prop traders, choosing the right lot size is crucial because it directly determines how much of your drawdown you risk on each trade. Trading too large a lot size relative to your account is the fastest way to blow a challenge. A common approach is to calculate lot size based on a fixed risk percentage and your stop loss distance.

PropJournal helps by automatically calculating your ideal lot size based on your account rules, current drawdown usage, and the specific trade setup you're planning. This takes the guesswork out of position sizing and keeps you within safe risk parameters.

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