If you need to convert between units of weight, use our kilos and pounds converter. To calculate your BMI. Divide your weight (lb) by your height (in). Example: 154lb ÷ 71in = 2.169; Divide your answer from part 1 by your height again. Example: 2.169 ÷ 71 = 0.03055; Multiply your answer from part 2 by 703. Example: 0.03055 × 703 = 21.48 Your ideal weight should be between 107.8 and 163.1 pounds. The average ideal weight should be 132.6 pounds. Stones and pounds (st & lb) Your ideal weight should be between 7 stones and 9.8 pounds and 11 stones and 9.1 pounds. The average ideal weight should be 9 stones and 6.6 pounds. Kilograms (Kg) Your ideal weight should be between 48.9 kgs Convert 86 Kilograms to Inches (kg to in) with our conversion calculator and conversion tables. To convert 86 kg to in use direct conversion formula below. 86 kg = 3385.8267716535 in. You also can convert 86 Kilograms to other Weight (popular) units. .