Carbon Interface - Measure carbon emissions with an API
SmogWise - SmogWise offers an alternative to traditional emissions testing by providing consumers with a simple, more affordable way to know if their vehicle is ready for testing, and with participating jurisdictions, a way to submit results directly.
Website Carbon Calculator - Find out the how much CO2 your website emits
Trip to Carbon - A carbon footprint calculation API for travel.
Stripe Climate - Remove carbon as you grow your business
Klima - Go carbon neutral