Product cannibalisation
Product cannibalisation is a new product taking sales from a store's existing products instead of bringing in extra sales.
How it works
During catalogue renewal, a store may add a product that meets the same need as an old one, such as a second frying pan. Some buyers switch from the old pan, so total sales grow by less than the new pan sells, or not at all. Sales won from competitors don’t count.
To check it, compare sales by product before and after the launch for every product the new one could replace. A fall alone proves little: in our study of 1.4 million products, the median stable winner held that status for only 3 months.
Store-level data shows the overall result, not who took buyers from whom. Our analysis of 100 stores compared the first three months of June 2025 – June 2026 with the last three. In stores that doubled revenue, old products brought in 126% of their starting revenue, with new products on top. In declining stores, the figure fell to 28%.
The full analysis is in do new products cannibalise your bestsellers.
Formula
Cannibalisation rate = sales lost by existing products ÷ sales of the new product
It is the share of the new product’s sales taken from the store’s existing products.
Example
Example store, not client data.
The tableware shop sold 50 of its old frying pans a month. A new pan then sells 40 in its first month, and the old one drops to 30. The old pan lost 20 sales: cannibalisation rate = 20 ÷ 40 = 50%. Pan sales went from 50 to 70, a net gain of 20.
Not to be confused with
- Campaign overlap — one product served by two of your campaigns, which split its clicks and data. Cannibalisation splits buyers between products.
Right and wrong readings
- Wrong: “The new pan sold 40, so the launch brought 40 extra sales.” Right: the range gained 20, because the old pan fell from 50 to 30.
- Wrong: “The old pan’s sales fell after the launch, so the new one took them.” Right: check earlier months first, because a bestseller often leaves the top within months anyway.
Sources
- Cannibalization — Universal Marketing Dictionary, after Farris et al., Marketing Metrics (2010): the definition, which excludes sales taken from competitors. Checked 2 October 2026.
- GetProfit study: 1,404,808 products in 130+ stores over 13 months — how long winners hold their status.
- GetProfit data: 100 online stores, June 2025 – June 2026, first and last three months — revenue from old and new products.