This pair is useful because the gross profit is easy to see while the two percentages are clearly different. Every result below comes from the same cost 60 and selling price 100, so no currency conversion, tax rule, or hidden fee is involved.

Subtract cost to get profit 40

Gross profit is selling price minus direct cost: 100 − 60 = 40. This amount is the numerator for both margin and markup. Keeping one profit amount prevents the two percentage formulas from drifting apart.

Use price for margin and cost for markup

Margin is 40 ÷ 100 × 100 = 40%. Markup is 40 ÷ 60 × 100 = 66.666667%. The dollar profit is identical; only the denominator changes. Calling both numbers “profit percent” would hide the decision that matters.

Check the multiplier and reverse the result

Price divided by cost is 100/60 = 1.666667. A 66.666667% markup adds approximately 0.666667 of cost, producing the same multiplier. A 40% margin also implies cost is 60% of price, so 60/0.60 returns exactly 100 before display rounding.