GMV is vanity; contribution margin is sanity.
An online platform sits between buyers and sellers and keeps a slice of every transaction. The headline number everyone quotes, gross merchandise value, is mostly vanity, because it is easy to buy growth by subsidising customers into a loss. The honest question is whether the platform keeps more of each order than it spends to serve it, and whether customers come back on their own instead of being paid to return. Repeat purchases lower acquisition cost over time and are the real compounding engine; without them the model is just burning cash for GMV.
An e-commerce platform is a middleman that connects buyers and sellers online and takes a cut of every transaction that happens through it. The tricky part is that it is very easy to fake growth in this model by simply spending more money than you make on each order.
Gross merchandise value (GMV) is the total value of everything sold through the platform, including the part that goes to sellers, delivery partners, and payment processors. It is the headline number every company loves to quote because it always looks big and growing. But GMV is not revenue, and it is definitely not profit, it is closer to the total volume of traffic passing through a toll booth, not the toll collected.
Give people a big enough discount, a 50% off coupon or free delivery, and they will buy almost anything, which is why GMV growth funded by subsidies is not proof of a good business. The real test is whether customers come back and buy again once the discounts fade, because that is what separates an actual habit from a one-time bargain hunt.
Take rate is the company's revenue divided by GMV, the slice of every transaction the platform actually keeps for itself, through commissions, delivery fees, and advertising sold to sellers. A rising take rate usually means the platform has built enough scale or trust that it can charge sellers and buyers more without losing them, a sign that monetisation is maturing.
Contribution margin is revenue from an order minus the variable costs of fulfilling it: delivery, packaging, payment processing, discounts. If this is negative, the company loses money on every single order before even counting fixed costs like salaries and warehouses, meaning more sales literally means more losses. Positive contribution margin is the first real proof that the business model can work at all.
Many e-commerce companies chase GMV and user counts to raise the next funding round, using investor money to subsidise prices below what the business can sustain. This works as long as new funding keeps arriving, but the moment it slows, discounts have to shrink, and a chunk of the demand that was only there for the subsidy disappears with it. The company that looked like it was scaling was really just renting customers.
Because these companies often lose money for years, valuing them on earnings does not work early on. Instead, track the trend: is contribution margin improving order by order, is CAC (the cost to acquire each new customer) falling as repeat purchases rise, and is there a believable, funded runway to turn overall profitable, cash burn, not GMV, before the money runs out. A shrinking loss with rising repeat rate is worth more than a bigger loss with bigger GMV.
Every sector reduces to a demand metric, a pricing metric, an efficiency metric, a capital metric, and a risk metric. For e-commerce, these are the ones that matter.
What each number tells you, and how to read it.
| Metric | Why it matters |
|---|---|
| GMV (Gross Merchandise Value) | Total transaction value on the platform. A scale metric, but inflated by high-return categories. Watch take rate. |
| Take Rate | Revenue over GMV, how much of each transaction the platform keeps. Rising take rate means monetisation is working. |
| CAC (Customer Acquisition Cost) | The cost to win each new user. Rising CAC with flat repeat rates means the unit economics are breaking. |
| Repeat Purchase Rate | Loyalty. High repeat means organic growth and lower CAC over time, the compounding engine. |
| Contribution Margin | Revenue minus variable cost per order. Positive is a path to profit; negative means still subsidising growth. |
| Logistics Cost | A major expense. Owning versus outsourcing logistics changes the margin structure; higher order density lowers per-unit cost. |