What is Real Costs?

Real Costs

is a Firefox plug-in that inserts emissions data into travel related e-commerce websites. The first version adds CO2 emissions information to airfare websites such as Orbitz.com, United.com, Delta.com, etc. Following versions will work with car directions, car rental, and shipping websites. Think of it like the nutritional information labeling on the back of food... except for emissions.

Download Now :

For Developers :

Current Greasemonkey Development Snapshot:


Requires Greasemonkey

This is like the source code for the plugin
Developer? Get in touch: Michael [a] Mandiberg [*] com Unsure what this is? you probably should click above.


Current version (v0.0.6) is beta. It works on these websites


Air Travel

Driving Directions


Car Rental

How Real Costs works:

Experience the project by installing the Real Costs plug-in into your Firefox application. Currently, this plug-in pulls each flight origination and destination information from the page, calculates and reinserts the CO2 produced. It compares the CO2 produced for that flight to making that trip by bus or train, and to the average CO2 produced per capita for the average US and world citizen. It is configured to work on the websites of the largest North American air carriers (major global air carriers to be added shortly.) A list of these carriers and documentation of all scientific calculations is available on the project Wiki.

Why Real Costs matters:

The objective of the Real Costs is to increase awareness of the environmental impact of certain day to day choices in the life of the Internet user. By presenting this environmental impact information in the place where decisions are being made, it will hopefully create an impact on the viewer, encourages a sense of individual agency, and provides a set of alternatives and immediate actions. In the process the user/viewer might even be transformed from passive consumer to engaged citizen.