Slow cooker reviews: Features explained

Round slow cooker for stews

A round slow cooker is best for stews and curries

Below, we highlight the features and specifications you should consider when buying a new slow cooker. 

Once you've decided the size and type of slow cooker you need, head straight to our full slow cookers reviews to find out how different models have done in our tests, including the slow cookers you should avoid. If you'd like to find out which slow cookers excelled, head straight to our list of slow cooker Best Buys.

Slow cooker size

Slow cooker sizes vary. The largest are around 6 litres, with a useable volume of 4.5 litres. This can contain enough stew for six to eight adults.

Common smaller sizes include 3.5-litre cooking pots with a useable volume of 2 litres. These are large enough to feed at least two people.

Oval slow cookers vs round slow cookers

Round slow cookers are best for cooking stews or curries, but oval slow cookers are more common and can accommodate joints of meat for roasting.

Slow cooker settings and functions

Auto cook

Not all models have this setting, but Which? slow cooker tests found the food cooked on auto cook was be better than food cooked using either the high or low setting continuously. 

The auto-cook setting starts cooking on high and after an hour continues to cook on low.

Slow cooker cheap meat

Slow cook cheap cuts of red meat on the low setting

Low setting

This is recommended for cooking cheap cuts of red meat as it breaks down the connective tissues and gets better results than cooking on the medium or high setting. 

Cooking on this setting usually takes around 10 hours.

Med (medium) setting

Use the medium setting for cooking cuts of red meats.

This setting is useful for cooking faster without losing all the benefits of slow cooking, but the results won’t be as impressive as cooking on low for longer.

Hi (high) setting

This is recommended for cooking pale meat such as chicken. It cooks the meat faster (in three to six hours) and at a slightly higher temperature.

Keep warm

A keep-warm or hold setting prevents food from drying out if your diners are delayed, but stops it getting cold.

Timer dial on Crock-Pot slow cooker

Most slow cookers have a timer that you can set

Other slow cooker features to look for


Not all models have a timer, but it's useful if you are going to be away from the slow cooker for longer than the recipe states. Once the cooking time you've set on the timer has been reached, the slow cooker switches to a 'keep warm' setting. This means your food will still be ready to eat as soon as you are, without it getting overcooked.

'On' indicator light

An indicator light is a good visual indicator that your slow cooker is working. This is useful as they take a while to warm up and you won’t be able to tell straight away that cooking has started.

Cord length

Make sure your slow cooker cord will easily reach a power point in your kitchen. Extension leads are dangerous, as liquids can be easily spilt onto them. 


Check your instructions. For some, only the lid is dishwasher-proof. If your cooking pot isn’t dishwasher safe, fill it above the cooking line with warm water and a dash of washing up liquid. Burnt-on remains should just slide off with minimal soaking.

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