Buying
Why cost per wear is the wrong maths
The favourite sum of the justified purchase leaves out the one number a handbag has and a T-shirt does not: what someone will pay you for it later.
The Worth the Bag team, 31 Oct 2026
Cost per wear is the one sum in fashion you do after you have already decided. Price divided by wears, a small answer, card out. It is a tidy little ritual, and for a handbag it gives the wrong result.
The idea has respectable origins. In 2016 Livia Firth was asking shoppers to stop at the moment of purchase and wonder whether they would wear something a minimum of 30 times. As a brake on fast fashion, that question earns its place. A T-shirt bought, worn and thrown away really does cost what you paid for it, because nobody is waiting to buy it back.
A bag has a second act. When you are finished with it, it is still an object someone may pay for, sometimes a great deal. The classic formula treats that money as if you had set fire to it.
The number it leaves out
Put the money back and the sum changes shape:
(price minus resale value) divided by wears
We did not invent this. Vestiaire Collective used the same formula in its 2024 circularity report. Vestiaire sells second-hand fashion, so it has its reasons for liking the answer, but arithmetic does not care who holds the pencil.
We call the result true cost per wear, and the difference becomes obvious the moment you run it on two bags.
An example, with made-up numbers
Everything in this table is hypothetical. These are round numbers chosen to show how the sum behaves. They are not the prices of any real bag and they say nothing about what any real bag will fetch.
| Bag A | Bag B | |
|---|---|---|
| Price | €6,000 | €2,000 |
| Wears over three years | 300 | 300 |
| Cost per wear | €20.00 | €6.67 |
| Sold after three years for | €4,800 | €400 |
| What owning it cost you | €1,200 | €1,600 |
| True cost per wear | €4.00 | €5.33 |
The old sum says Bag B is three times cheaper. The better sum says Bag A cost you less to own. Nothing changed but the question.
The old sum says Bag B is three times cheaper. The better sum says Bag A cost you less to own.
Are gaps that wide realistic? Resale does vary enormously by label. Rebag’s first Clair report, published in 2020, put Hermès at nearly 85 percent of the original price, Chanel and Louis Vuitton at around 65 percent, and one 2019 Bottega Veneta bag at 27 percent. Those are one reseller’s figures and they are six years old, so read them as proof of spread and nothing more. Our own value index shows what the listings say now.
Where the better sum can flatter you too
True cost per wear has one soft number in it, and you are the person typing it in.
Resale is what reaches your account after fees, which is rarely what a listing asks. A seller who enters the asking price of the prettiest example on the internet has written fiction with a decimal point.
Resale also moves, and it moves after you have paid. Bernstein’s tracker, as reported by The Fashion Law, shows Birkin and Kelly bags reselling at about 2.2 times retail in 2022 and roughly 1.4 times by November 2025. Anyone who ran this sum in 2022 with that year’s multiple was using a number that no longer holds. We looked at that fall in why the Birkin premium fell.
Then there is the awkward case. If you will never sell the bag, its resale value is a compliment and not a sum. Plan to leave it to your niece and the old formula is the honest one, so use it with a clear conscience.
Neither version tells you whether you can afford the thing. Bag A in our example still needs €6,000 on the day you buy it, and a low true cost per wear does not pay a card bill. It is also not a reason to treat a handbag as a financial product. Prices fall as well as rise, and past resale says nothing certain about future resale.
Do it with your own numbers
The fair use of this sum is as a comparison between two bags you already want. Pick realistic wears, because three hundred is two outings a week for three years and most of us are not that loyal. Pick a resale figure you would defend to a friend. Then look at both answers side by side.
Our cost per wear tool does the arithmetic with your numbers, with no email address required. Item pages show the same logic on a receipt, built from historical asking prices with the sample size printed beside them. That is historical data, with no forecast attached.
The old formula asks how often you will carry it. The better one also asks what happens when you stop.
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