What if you could see – in kilograms – the amount of C02 emissions involved in purchasing a new pair of jeans?

Swedish payments firm Klarna has just added such a feature to its app, offering each of its 90 million users the option of monitoring the carbon footprint of their purchases - from production to delivery at the consumer's front door.

The feature will display an estimated carbon emission for individual purchases and also allow users to track their cumulative carbon footprint over months.

The figures will be compared to energy burning activities such as a car journey of a certain distance, so the cost can be better understood.

Klarna Chief Executive Sebastian Siemiatkowski.

"So what we decided to do is basically partner up with somebody called 'Doconomy' and what they have, they're enabling us to basically be able to calculate the carbon footprint of every purchase that you would do with Klarna - it's 90 million consumers doing two million purchases per day. And then make it transparent to them, similar to when you buy groceries you can see what's the you know nutritional impact of the decision of buying this product with sugar or fat or whatever it might be, and just show them the carbon footprint consequence of their purchase. And so we think this could be a very powerful thing and help provide that transparency and educating people about the impact of their decision."

The firm, which counts retail giants H&M and ASOS among its quarter of a million clients, said users will currently only see the emissions after a purchase, but that it hopes to update the app so it is shown in advance.

This could result in shoppers comparing the carbon emissions of rival products before selecting which item to buy.

Shoppers will not be charged money to use the app's CO2 tracker, Klarna said.

"To us this is about competitiveness. I think people want, we see - we asked 65 percent of our millennial users and GenZ using our products about how important this is, like it ranks among the absolute biggest requirements of theirs and interests of theirs to understand these kinds of things."

Klarna’s buy-now, pay-later credit system has been criticized in Britain for encouraging debt among young people.

In February, the British government said it would introduce regulation forcing firms like Klarna to make affordability checks before lending to a customer.