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One day, the internet will be powered by renewable energy. Until that day comes, there’ll be a CO2 cost that comes with every byte of data that’s uploaded or downloaded. By being able to calculate these emissions, developers can be empowered to create more efficient, lower carbon apps, websites, and software.

What is CO2.js?

CO2.js is a JavaScript library that enables developers a way to estimate the emissions related to use of their apps, websites, and software.

Why use it?

Being able to estimate the CO2 emissions associated with digital activities can be of benefit to both developers and users.

Internally, you may want to use this library to create a carbon budget for your site or app. It is also useful for inclusion in dashboards and monitoring tools.

For user facing applications, CO2.js could be used to check & block the uploading of carbon intensive files. Or, to present users with information about the carbon impact of their online activities (such as browsing a website).

The above a just a few examples of the many and varied ways CO2.js can be applied to provide carbon estimates for data transfer.

How to use it

To get started using CO2.js, refer to our developer documentation.

If you’d like to view our open source repo, you can see it in GitHub.

If you’re using CO2.js in production we’d love to hear how! Drop us a line.

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