คำนวณขนาด Lot ที่เหมาะกับคุณ

What is position sizing / the right lot size?

Position sizing is choosing the lot size of each order based on your account balance and the percentage you are willing to risk per trade. The goal is to keep the amount of money at risk constant on every order, no matter which pair you trade or how wide your Stop Loss is. By fixing risk as a percentage of the account, the lot size adjusts itself to the SL distance, so risk management stays consistent and is not driven by emotion.

How do you calculate lot size by risk?

Use the formula: lot size = (balance × risk %) ÷ (Stop Loss in pips × value per pip). Example: a $1,000 account risking 1% can lose $10 per trade. With a 50-pip SL on a micro account worth about $0.1 per pip, that is $10 ÷ (50 × 0.1) = $10 ÷ 5 = roughly 2 micro lots. (This is an illustrative example only; the real value depends on the pair and account type.)

How much should you risk per trade, and why does a wider SL mean a smaller lot?

Many traders cap risk at around 1–2% of the account per trade so a losing streak is survivable. When the Stop Loss is wider, the divisor in the formula grows, so the lot size automatically shrinks to keep the money at risk the same. Adjust balance, risk %, and SL in the calculator above to see the lot size that fits your plan.