Margin and Markup Are Not the Same Number

The difference is the denominator

Markup is profit as a share of what the item cost you. Margin is the same profit as a share of what you sold it for.

Since price is larger than cost, the same profit is a smaller fraction of price than of cost. So margin is always the smaller number and markup always the larger. They're equal only at zero.

A $60 item sold for $100 makes $40 either way. That's a 40% margin and a 66.7% markup — both correct descriptions of the same sale.

The conversion, worth memorising

margin = markup ÷ (1 + markup) markup = margin ÷ (1 − margin)

Markup	Is really a margin of
20%	16.7%
30%	23.1%
50%	33.3%

Margin	Needs a markup of
10%	11.1%
50%	100%
80%	400%

If you've ever priced at "cost plus 30%" believing you were making 30%, you were making 23%.

⚠️ The error only runs one way

Markup is always the larger number. So mistaking one for the other means you charged less than you intended — never more.

And it doesn't announce itself. The sale still happens, the customer is happy, and the shortfall shows up only as a business that's somehow busier than it is profitable.

Here's the money. A $60 cost with a 50% target:

Priced correctly (margin)	Priced as a markup
$60 ÷ 0.5 = $120	$60 × 1.5 = $90

A $30 shortfall on every single sale. Multiply that by monthly volume before deciding it's small.

Price with the divide, not the multiply

To hit a target margin: cost ÷ (1 − margin).

Not cost × (1 + margin) — that's the mistake, and it's an easy one to make because the multiply feels like the natural operation.

The gap explodes at higher margins

At a 10% margin you need an 11% markup. Close enough that confusing them costs little.

At 50% margin you need a 100% markup.

At 80% margin you need 400%.

So anyone selling high-margin goods or services who reasons in markup is working with numbers that bear almost no resemblance to their accounts. This stops being a rounding issue very quickly.

The same arithmetic explains why discounts hurt

Once you're thinking in margins, one thing follows immediately and it's worth seeing.

A discount comes entirely out of profit. Your costs don't move, so every dollar off the price is a dollar off the margin — which means a small discount is a large profit cut.

That same $60 cost and $100 price, at a 40% margin:

Discount	New price	Profit	Profit cut	Extra sales to stand still
5%	$95	$35	13%	14%
10%	$90	$30	25%	33%
20%	$80	$20	50%	100%

A 10% discount costs a quarter of your profit, and you'd need a third more sales just to end up where you started. A 20% discount means selling twice as much for the same money.

And the lower your margin, the worse this gets — at a 20% margin, a 10% discount halves your profit.

That's not an argument against ever discounting. It's an argument for knowing the number before you agree to one.

Which should you actually use?

Both, for different jobs.

Markup is a pricing mechanism — a convenient way to get from a known cost to a price. Nothing wrong with using it, provided you know what margin it produces.

Margin is what the business runs on, because it's the share of revenue you keep. Fixed costs, break-even, and your ability to absorb a bad month are all measured against revenue rather than cost of goods.

Set prices with markup if that's easier. Judge the business on margin.

This is gross, not net

Cost here means the direct cost of the thing sold. Rent, wages, software, insurance and marketing all come out of the margin afterwards.

So a healthy gross margin isn't the same as a profitable business — it's the starting point from which everything else gets paid.

It also means "we make 40%" is ambiguous twice over: which of the two numbers, and which costs have already been deducted.

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This is general information, not financial advice. Pricing interacts with tax, competition and your own cost base in ways no calculator sees — if a pricing change matters to the business, it's worth talking through with a qualified adviser or accountant.