Which? Research Find out more about how Which? tests products and services, and carries out undercover investigations. Also, details on the symbols and star ratings used in Which? reviews
At Which? we test more than 2,500 products every year, from toasters to cars and everything in between - but we don't stop there. We also put service providers under the microscope, assessing their quality of service provision, terms and conditions, and customer satisfaction.
We spend around £3.5m on research each year and whether we're conducting an undercover investigation or simply buying products we send to our labs, everything is done anonymously and independently. Each of the products that we lab test are bought from regular sources: places where typical consumers might shop, such as everyday high street shops and online retailers.
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More than 50 years of testing experience
Set up in 1957, Which? has more than 50 years of testing experience. The controlled testing methods we use means our tests can be replicated time and time again. This ensures that each product we test within a category, is assessed in the same way - meaning that if you want truly comparable reviews, then you need look no further than Which?
But we go beyond simply saying which products are good and which are bad; when our research is complete we willingly share our findings with manufacturers to help them improve their products. What's more, we also speak to the relevant governing bodies if our research exposes malpractice or shoddy products.
Nobody else tests like Which?
We use a number of research methods and approaches. And we employ people with expertise across a wide range of areas from nutrition to finance, plus technical experts in social research, science and statistics. We continually innovate to find the best approaches to identify and investigate the issues that matter.
Our most common methods are detailed in the pages on the left, but we also use focus groups and diary keeping. Last year we gathered 34,626 diary entries from 4,000 members detailing their experiences with royal Mail.
When selecting products to test, we take into account the top sellers on the market, as well as any products that offer new and innovative features. We also take into account feedback from our members, and make sure that the products we test are the ones that they want to see.
When testing cars we evaluate them on the road and in a lab. We independently test around 140 cars each years, and our annual car survey collects data on around 50,000 cars, meaning that users' views influence the results. You can find out more about how we test cars and are car survey here.
In short, our experience and expertise enables us to select the best approach to testing products and services, in a way that nobody else can. And whatever the method, whatever the topic, all our research is underpinned by some key principles, in particular: quality, integrity, relevance and impact.