Lot size calculator
Size every position from your risk, not your gut — balance, risk % and stop-loss in, lot size out. Professional traders size positions from risk: decide what fraction of the account a losing trade may cost, and let the stop-loss distance dictate the lot size.
Account currency: USD · standard MetaTrader contract sizes. Estimates for guidance only — actual values depend on the instrument specification and your account type in MT4/MT5.
How it works
- Amount at risk = account balance × risk %.
- Lot size = amount at risk ÷ (stop-loss in pips × pip value per lot).
- For USD-based pairs like USDJPY the pip value itself depends on the current price — the calculator handles it.
Frequently asked questions
What lot size should I trade?
Size from risk, not from margin: most professionals risk 1–2% of the account per trade. This calculator turns that percentage and your stop-loss into an exact lot size.
What is 0.01 lot?
0.01 lot — a micro lot — is 1,000 units of an FX pair (about $0.10 per pip on EURUSD) or 1 oz of gold. It is the minimum size on most TNFX accounts.
Why does my stop-loss distance change the lot size?
The wider the stop, the more pips a losing trade covers — so the same dollar risk must be spread over more pips, meaning a smaller lot. A tight stop allows a larger lot at equal risk.