We've tested hundreds of detergents over the years, and publish new laundry detergent reviews every year because, along with your washing machine, a top performing detergent is the key to clean clothes. Detergent also makes up a third of the running cost of your washing machine.
Why do we need to test so often? While you may have your favourite detergent that you've been using forever, that brand's current formula probably has no relation to how it was formulated five years ago. Advances in chemical technology mean that you can't rely on your favourite brand to stay the same, because they're always trying to beat the competition – which is why we test so often.
One of the big questions is what kind of stains is your laundry detergent best for? This depends on the stain type and the detergent. Do you work in a surgery? Do you have children? Do you regularly spill chocolate ice cream? Are you a chef? These all result in different types of stains. It's also why we ask you via Voice Your Choice which stains you get the most.
With over 30 years' experience in the laundry lab, we're proud of our expert testers. They've seen all types of laundry detergents come through the labs, but one thing never changes – they need to find what gets your clothes clean. We focus on the basics so that when it's time to buy, you can be sure the laundry detergent you buy will work well.
Why do we choose one laundry detergent over another? There are a number of reasons for this, but our priority is to test what you'll see at the shops. This usually includes well known detergent brands like Cold Power, Dynamo, Drive and Omo, along with major grocery store brands like Aldi, Coles and Woolworths. This means you can see it before you buy it and check whether you're happy with it.
How do we know what's in retailers? We check current market figures to see what's selling well. We'll also include detergents that you've requested – if a lot of members want it, we'll test it.
Once we know what you want to read about, our buyers use your member fees to buy the laundry detergents anonymously from a variety of retailers, then bring them in as is. This means we get what you'd get, so we can be sure the results are what you'll find rather than potentially 'tweaked' for better performance.
Contrary to popular opinion, we don't get CHOICE employees to bring in their dirty laundry. We use set loads of cotton materials, and attach a variety of pre-stained fabric swatches to them. These stains are made in the Netherlands and include the most common stains as chosen by you, our members. Why do we use pre-stained swatches? Because comparing laundry detergents fairly means you have to use identical conditions for all of them.
The swatches of cloth that are embedded with a specific amount of dirt are identical and made up of a very specific formula. These are used all over the world by large detergent makers, plus other consumer organisations and are considered a standard in testing detergents. Using them minimises the amount of variables so you can see which detergent comes out best when comparing them.
After we put the recommended dose of detergent in either a front loading washing machine or a top loading washing machine (we have four identical washers of each type so there is minimal difference in machine type), we use a cold wash (20°C) on a standard wash for our testing.
Once we run the wash, we retrieve the stained swatches and compare how clean they are post wash to how dirty they were pre-wash. We use a spectrophotometer to measure the difference which is a better measure than the human eye.
Stain selection and weighting
This is the list of swatches we use when testing laundry detergents. They usually change every few years in response to surveys we send out to CHOICE members.
- General detergency (35%)
- Sebum – natural oils, perspiration (20%)
- Grass/mud (15%)
- Olive oil (6%)
- Makeup (4%)
- Chocolate ice cream (4%)
- Baby food (4%)
- Aged blood (4%)
- Mineral oil (4%)
- Tomato (4%)
There are a variety of reasons for this, but it mostly comes down to subjectiveness. Some detergents are strong sellers in the market, so we assume many people don't care about the smell, or don't think it's strong. There would be other people who do think a smell is overpowering. How do we make an assessment on what's strong and what's OK?
We've contacted professional fragrance makers about this aspect, and really they could only tell us what the fragrance is supposed to be representative of in terms of fragrance type (lemon, orange, etc), not strength of smell.
This will also depend on how old the detergent is – the newer the box is the more likely it is to have a strong smell, because fragrance fades over time. Many manufacturers aren't too transparent about when something is made, so if we found one was strong, and another was weak (assuming we even could) then it could be based on how old the box is. That kind of assessment wouldn't be fair to the manufacturer or our members.
CHOICE tests within all the variables we can control. We use the same stain swatches, washing machines, testers, temperature and humidity, hardness of water, ballast (the load that we attach the stains to) and methodology. We even buy all the products the same way you would so it's a more realistic result. And yet year on year we will commonly see a brand/model of detergent change.
One thing that CHOICE doesn't have control over is the formula that each manufacturer uses for their detergent. We don't know why some manufacturers will adjust their formula throughout the year. We've chatted to industry experts who have said that it might be their supplier contracts changing or trying to improve their results by adjusting their formula. In some cases they may order their formula ingredients through a third-party supplier and not even know that the supplier has changed their suppliers.
This is why we test the entire market available in national retailers each year so we can identify these changes in the manufacturer formula. It can be frustrating to see that your brand or detergent type has changed performance results, but it's also why we keep testing – so you know when to switch to the better performing detergent.
We maintain a lab that is up to date with the latest reference machines and calibrated measurement tools for our testers to bring you the right results.
Stock images: Getty, unless otherwise stated.