How we test slow cookers
By Yvette Fletcher
Find out how we uncover the slow cookers that are worthy of space in your kitchen.
Our slow cooker tests show that you don't need to buy a premium or big-brand model to get a slow cooker that can make hearty stews and casseroles. We've tested affordable own-brand machines that work as well as - or better than - models costing more than double the price.
Every slow cooker that passes through the Which? test lab is subject to 70 different assessments to ensure it cooks well and is easy to use. Our reviews answer the most crucial questions you have about slow cookers, including:
- How well does it cook stews and casseroles?
- How well does it roast?
- How easy is the slow cooker to set up for cooking, and to clean afterwards?
- How useful are the instructions?
- Should I buy it?
Find out which models give top-class results in our slow cooker reviews.
How well does it cook stews and casseroles?
We test slow cookers on both their high and low settings by cooking a beef stew. We check how long it takes for the stew to be cooked on each setting and assess whether it's evenly cooked, with tender meat and a rich and tasty sauce. Good models will apply the temperature evenly so you won't find certain pieces of meat overcooked or undercooked, and you won't find the sauce watery or lumpy.
Once we've tested each setting, we'll also test the slow cooker's 'keep warm' setting (if it has one) for an hour to ensure that it can keep your food at a good temperature without drying it out.
How well does it roast?
You might not have thought to roast meat in your slow cooker, but it's an energy-efficient way of doing so. If a slow cooker is capable of holding a whole chicken, we test how well it roasts. We time how long it takes for the chicken to be cooked completely, check its temperature and assess how evenly it's cooked.
Roasting chicken in a slow cooker gives different results from oven roasting - chickens come out paler in a slow cooker, with far less crisping in the skin. However, some slow cookers produce chickens that look more appetising than others. Some will undercook or overdo the chicken - the meat will be difficult to remove from the bone, or seem shrivelled and dry.
How easy is it set up and clean?
A slow cooker can be a convenient way to knock up healthy meals. The best are easy to set up and use and a breeze to clean. To compare models, we check how easy it is to fit the parts together and how clear the settings are. Good ones will have clearly labelled controls and the pot will fit onto the base easily.
We know you don't want a cooker that's a drag to clean up - we check whether the pot and lid are dishwasher-safe and can be fully immersed in hot water for cleaning. Sometimes the base can have dirt traps or be tricky to keep clean.
How useful are the instructions?
In terms of controls and set-up, slow cookers aren't that complicated. But where you might want clear guidelines is around which settings to use for different foods (and for how long), how to convert your favourite recipes for use in a slow cooker, and some suggested slow-cooker recipes to help you get started.
We check the instruction manual provided with each slow cooker to make sure it gives adequate usage guidance, so you can get the best out of your new gadget.
76%The test score that a slow cooker needs to earn to be named a Best Buy.
Should I buy it?
All the tests above contribute to the final overall test score for each slow cooker we review. Because we know some things are more important to you than others, some elements are given a greater weight in our test score.
- 60% cooking
- 30% ease of use
- 10% build quality
Only slow cookers that score 76% or above can be a Which? Best Buy.