The desire to be ethical consumers has gone beyond the realm of Fairtrade bananas and organic tomatoes. Many are now questioning the environmental and ethical implications of their investments, no matter how small.

The Cooperative Bank and Triodos are two well-known examples of ethical and ecofriendly banks – Cooperative offers a full range of conscience-salving banking products and Triodos has several savings accounts.

But beyond these, how do you know that you are putting your money in ethical hands? Corporatecritic.org is the most thorough website devoted to such queries. It keeps tabs on the corporate social responsibility (CSR) of more than 50,000 companies, from small independent start-ups to multinationals. Companies are scored on their performance and history in five categories: environment, people (human rights, workers’ rights, armaments), animals, politics (genetic engineering, boycotts, company ethos) and product sustainability.

Users can customise scores by selecting a category, or by rating the importance of each from “ignore” to “high”. This enables you to search companies selectively – how does Barclays rate on armaments, or Lloyds TSB on workers’ rights? In practice, however, it makes more sense to let the site do a full search, since the results are presented by category with a number next to each. Simply click on the company’s name for more information and the reports about the company that contributed to its rating.

The depth of the information is impressive. For example, a search on Lloyds TSB reveals an overall score of 13 (perfect ethics earn a score of 20). On workers’ rights (one of 17 sub-categories), the death of a worker on a job in India in 2005 and a court case brought by an employee suffering from stress in 2000 contribute to a low score of minus two, but we also learn that Lloyds is among the top ten companies for promoting diversity in the workplace.

The score awarded to each company by corporatecritic. org is called an “ethiscore”, the invention of its sister site, ethiscore.org. This guide dredges up less information and is simpler to use than corporatecritic, but it is not short on details. The ratings are determined by CSR and product sustainability – two categories, rather than five.

The site has a fun side, too. Each day it features a product and a list of ethiscores for different brands. For example, Peter Rabbit Organics Chocolate Bar, with a score of 15.5 out of 20, is the most ethical chocolate on the market. In last place is Nestlé’s Yorkie bar – sins include failure to act on the palm-oil environmental threat and the use of animal byproducts.

Case study: I can make a difference

Until recently Helen O’Malley never gave much thought to ethical investing. But the current wave of films and high-profile campaigns to raise awareness about the environment and human rights has given her pause for thought.

Ms O’Malley, a 25-year-old steel markets analyst, feels that she has enough disposable income to make a difference with her consumer choices. “When I am shopping at the weekend or considering my basic finances – such as where to go for an Isa – I like knowing a company’s ethical rating,” she says.

After checking on corporatecritic.org, Ms O’Malley has decided to rethink her choice of bank. “The ethiscore for my bank, NatWest, is only 12 out of 20”, she says. “I was also unimpressed to find that it is also Unilever’s bank, which had the worst rating in the pollution category in 2005.”