GreenFrame is a command-line tool that estimates the carbon footprint of web apps at every stage of the development process. Put it in your Continuous Integration workflow to get warned about “carbon leaks”, and force a threshold of maximum emissions.

For instance, to estimate the energy consumption and carbon emissions of a visit to a public web page, call greenframe analyze:

$ greenframe analyze https://marmelab.com
✅ main scenario completed
The estimated footprint is 0.038 g eq. co2 ± 1.3% (0.085 Wh).