The comparison feature is designed to push energy consumers into being more efficient with their energy use and will offer tailor-made recommendations to each household.
Opower managing director for Europe, Middle East and Africa, Nandini Basuthakur, said: "We've worked closely with E.on to design the saving energy toolkit with its customers in mind.
"Our expertise in behavioural science, data analytics and consumer marketing, combined with our successful utility deployments worldwide, have shown that customers are motivated to behave more like their peers - in this case efficient similar homes."
By using the new online toolkit, consumers will be able to compare their electricity and gas usage with 100 other anonymous E.on customers with similar sized and types of homes, as well as against the most energy-efficient home in their local community.
E.on sales and marketing director, Anthony Ainsworth added: "We've been speaking to our customers and it's clear from these conversations that there is wide-scale enthusiasm to have more insight and understanding about their household's energy use.
"We're committed to helping our customers use no more energy than they need and our online saving energy toolkit will help people achieve this."
The scheme gives E.on customers a breakdown of where and when they use the energy in their home and also presents them with a what uses most chart to compare heating, lighting hot water, appliances and other energy use.
It can also show customers a breakdown of costs month on month and offers them tailored tips on how to make their home more energy-efficient such as lowering their water temperature, ling drying laundry and installing loft insulation to keep the heat in.
As part of the Green Deal, E.on customers can also contact the firm about loans on energy-saving measures such as a replacement boiler and wall or loft insulation to further boost their home's energy efficiency.
Click here to run an energy price comparison, and see if you could be paying less for your gas and electricity.