Size = Balance * Leverage / (100,000 * StopOut + Pip_Value * SL * Leverage)
Size = $1,000 * 500 / (100,000 * 0.5 + $9.49 * 40 * 500) = 500,000 / (50,000 + 189,800) = 2.085 lots
StopOut = Equity / Used_Margin Equity = Balance - Loss Loss = Size * SL * Pip_Value Pip_Value = 1,000 / USDJPY_Ask = 1,000 / 105.331 = $9.49
SL = 40 pips Used_Margin = Size * 100,000 / Leverage StopOut = 50% = 0.5 Leverage = 500 Balance = $1,000
=E8*$G$1/(100000*$J$1+(E8/$F$4)*1000*$M$2*$G$1)