Camping & Outdoor Gear · Sizing
Cool Boxes & Coolers Sizes Explained
By the Nest & Yard editorial teamUpdated 2026-08-094 min read
Keeping food and drinks cold on a day out is essential for any camper or outdoor enthusiast, but choosing the right size cool box can be tricky. This guide breaks down how sizes are typically described – from compact cooler bags like the Vinsani 20L to larger electric models such as those offered by Vivo Technologies and iceQ – so you can confidently measure up before you buy. Understanding what the different litre measurements mean will help ensure you get a cool box that fits your needs and available space, whether you’re heading to the beach or on a family picnic.
See the full range in Cool Boxes & Coolers.

Currently unavailable
Pros
- 20-litre capacity is a good size for day trips and picnics
- Foldable, leakproof design stores flat when not in use
- Doubles up for keeping food warm as well as drinks cold
Cons
- Passive insulation only, so ice packs are needed for longer trips

#2 Pick
Electric Cooler Box of 26L, Large Cool Box Powered By 12V In-Car Cigarette Lighter Socket or UK 3 Pin Plug- 26L
Currently unavailable
Pros
- Heat function as well as cooling makes it useful year-round
- Runs from either a car socket or a home mains plug
- Roomy 26-litre capacity suits family camping trips
Cons
- Noticeably noisier than a passive cool box when running

Currently unavailable
Pros
- Dual power options work from a car socket or mains at the campsite
- 32-litre capacity holds a good few days of food and drink
- Lightweight body is easy to carry between car and pitch
Cons
- Thermoelectric cooling only chills below ambient, not a true fridge
FAQ
What does 'Capacity' mean when talking about cool boxes and coolers?
Capacity refers to the volume – typically measured in litres – that the cool box or cooler can hold. This is the amount of ice you’ll need to fill it for a specified period, not necessarily the total volume of the box itself.
How are cool boxes and coolers sized? What's the difference between Small, Medium and Large?
Generally, ‘Small’ cool boxes usually hold up to 30 litres, ‘Medium’ ranges from 40-60 litres, and ‘Large’ capacities typically exceed 70 litres – these are approximate guidelines.
I'm planning a picnic for two. What size cool box would you recommend?
For two people, a medium-sized cool box (around 40-50 litres) should be sufficient to keep drinks and some snacks chilled comfortably; anything smaller might struggle during a longer outing.
My family of four enjoys barbecues. What's the minimum size I’d need?
A large cool box, with a capacity of 70-80 litres or more, would be ideal for a family of four, allowing space for plenty of food and drinks without constantly needing refilling.
How do you measure up my storage space before buying a cooler?
Measure the internal dimensions (length, width, and height) of the area where you intend to store the cool box. Ensure it can comfortably fit with enough room for access and ice packs.
What does ‘Insulated’ mean in relation to cool boxes and coolers?
‘Insulated’ describes the material used in the walls of the cooler – foam or plastic – which helps slow down heat transfer, keeping contents colder for longer than a non-insulated box.
Are there different types of insulation? Does this affect how long things stay cold?
Yes, thicker foam provides better insulation than thinner foam; higher quality plastic also contributes to improved thermal performance, meaning it will maintain temperature stability for a longer duration.
How do I measure the size of a cool box I already own?
Measure its length, width, and height using a tape measure, noting these measurements in centimetres or inches. This helps you compare to new models’ specifications.
What about coolers with wheels? Do they need to be bigger?
The addition of wheels doesn't inherently increase the capacity; however, larger coolers with wheels are often easier to manoeuvre and may accommodate more ice due to their increased volume.
Can I use frozen gel packs instead of ice in my cool box?
Yes, frozen gel packs are a viable alternative to ice. Ensure they fit within the cooler's capacity and don’t block airflow, which can reduce cooling effectiveness.
In depth
Understanding Cool Box & Cooler Sizes: A Practical Guide
Cool boxes and coolers are invaluable for picnics, beach trips, camping, and even just keeping drinks cold in the UK summer. However, choosing the right size can be tricky – the marketing often uses confusing terms that don’t always align with real-world needs. This guide breaks down the common sizing conventions used on Amazon UK listings and provides practical advice to help you select a cool box or cooler suitable for your household and available space.
The primary measurement you'll encounter is volume, typically expressed in litres (L). This represents the total internal capacity of the cool box – how much it can hold. But don’t immediately jump to purchasing the biggest one; consider what you actually need to store. Small cool boxes, generally under 30L, are best suited for individuals or couples who primarily want to keep a few bottles and some snacks cold during shorter outings. Think of these as ideal for a solo hiker, a quiet afternoon in the park, or a couple enjoying a leisurely picnic where you won’t be filling the box to capacity. They're also good for smaller kitchens where space is at a premium; they are relatively compact to store when not in use.
Moving up to 40L – 60L cool boxes represents a significant step up in usability. This range becomes suitable for small families (two adults and perhaps one child) or individuals who regularly take larger quantities of food and drinks on trips. These sizes offer enough space to pack sandwiches, salads, drinks, ice packs, and still leave room for extras. Many retailers use the term ‘Medium’ for cool boxes in this size bracket – a useful shorthand but always check the actual litre capacity to ensure it meets your requirements. It's also worth noting that larger cool boxes within this range might be slightly less practical to transport without assistance.
Coolers exceeding 60L are generally designed for families or groups, particularly those who enjoy longer excursions like camping trips or extended beach days. These models often feature thicker insulation and robust construction to maintain cold temperatures for longer periods. You’ll frequently see terms like ‘Large’ or ‘Extra Large’ applied here. A 70L – 80L cooler could easily accommodate a family of four with plenty of food, drinks, and ice packs, while an 90L+ model would be suitable for larger groups or those requiring significant storage capacity. When considering this size range, carefully assess your transport options; these coolers can become quite heavy when full and require assistance to move.
A common mistake shoppers make is focusing solely on the external dimensions of a cool box – length, width, and height – without understanding its internal volume. Manufacturers often use rounded measurements or imprecise descriptions. Always check the litre capacity listed on the product page to ensure it aligns with your anticipated needs. Furthermore, consider that some cool boxes have shelves or dividers which reduce usable space. Some models may also include accessories like carrying handles or wheels; factor these into your overall assessment of size and portability.
Finally, think about where you intend to store the cool box when not in use. A large 80L cooler will be an eyesore crammed into a narrow hallway cupboard, while a smaller 30L model could easily find space under a bed or in a utility room. Measure your available storage space before making a purchase – this is crucial for ensuring you can comfortably store the cool box when it’s not being used. Don’t overlook vertical space; wall-mounted shelves or dedicated storage units are ideal solutions for larger models.
The Nest & Yard editorial team
Written and reviewed by our UK-based team of home improvement and gardening writers, who research specs, pricing and customer reviews before every recommendation. Reviewed and updated on 2026-08-09.