Households across Australia can now measure the impact of simple lifestyle changes on greenhouse gas emissions in as fast as 15 minutes through a groundbreaking online tool.

The Australian Greenhouse Calculator was officially launched at RMIT University this week by Victoria's Commissioner for Environmental Sustainability, Professor Kate Auty.

The AGC is a free and easy-to-use program to help households compare the impact of making lifestyle changes and/or investing in energy-efficient products - cutting both their greenhouse gas emissions and living costs.

Project leader, RMIT Adjunct Professor Alan Pears, said the AGC aimed to empower households by offering accurate and relevant information to help them see how their activities contributed to their carbon footprint.

"Australian households generate at least one-fifth of Australia's greenhouse gases - over 18 tonnes per household each year," Adjunct Professor Pears said.

"The Australian Greenhouse Calculator shows families how they can live more sustainably and offset the increasing cost of carbon and energy, helping them make lifestyle changes that are good for both the environment and their wallets.

"It's about inspiring real change - and then accurately calculating its impact."

The AGCis an Environment Protection Authority tool developed by RMIT's Centre for Design, through a project managed by Education Services Australia.

Professor Denise Meredyth, Deputy Pro Vice-Chancellor, Research and Innovation, College of Design and Social Context, said RMIT had a strong involvement in research and consulting on a broad range of sustainability issues, from life cycle analysis to smart grids and climate adaptation.

"The Australian Greenhouse Calculator reflects both our research commitment and our aim to encourage staff, students and the general public to 'think green' and make changes in their day-to-day lives to minimise their impact on the environment," Professor Meredyth said.

"Already, work done for the AGC has informed the development of other calculators, and the knowledge is feeding into improvements to our life cycle analysis database, and the research of our post-graduate students.

"Through the Centre for Design, RMIT is proud to support the development of the Australian Greenhouse Calculator and we hope to see this exciting new tool used broadly around the country to inspire - and measure - real sustainable change."

The AGC covers 11 lifestyle categories - transport, air travel, heating and cooling, hot water, clothes dryer, lighting, refrigeration, cooking, other appliances, food and shopping, waste - which can be completed in either a "quick" or "detailed" mode.

The "quick" mode can be completed in 15 minutes, for a general but thorough overview of greenhouse impact.

The "detailed" mode offers a full range of technical and behavioural options, for the ultimate domestic sustainability enthusiast.

Not just for households, the Australian Greenhouse Calculator is also an ideal tool for education, community engagement and encouraging sustainable business practice.

A "Research Centre" tab offers detailed background information on climate change, while "Teacher Ideas" includes educational resources and student activities.

The AGC also allows you to watch four animations to explore key issues relating to climate change.