What is a disposable nappy?

Disposable nappies are nappies that your baby wears once, and then get thrown away. Made of layers of paper, absorbent wood pulp and plastics, they usually contain a polyacrylate, which absorbs liquid and turns to a gel when wet, expanding and holding many times its own weight and volume in fluid.


Mums concerned about the environmental impact of disposable nappies, but who don't want to head down the reusable nappy route can also now opt for eco disposables, or part-disposable part-reusable nappies.


How old is your baby?

Disposable nappies come in a range of styles (and sizes) to cater to your baby's age and stage of development. The product names aimed at each stage can be decoded roughly into the following:


Names like ‘Ultra soft’ are common. And they are very soft, to protect ultra-delicate baby skin. They’re designed to absorb that soft sludgy newborn poo. The waistbands usually feature a U-shaped cutout so they won't irritate the delicate umbilical cord area.

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Young baby

You’ll see the word ‘dry’ – think 'Baby-Dry', 'Super-Dry', 'super dry' 'Simply Dry'. The focus is efficiently absorbing moisture so your baby won't feel wetness against his or her skin. 'Dry' ranges can cater for small babies right up to toddlers, so don’t feel you can’t use them if your baby’s older or younger.

Older baby/young toddler

Names include 'Active Fit', 'Natural Fit', 'Super Fit', 'Explore', 'active stretch'. They're designed to be leak-proof while your baby crawls, cruises, climbs or runs around. They're thinner, less bulky and have stretchy leg-holes to allow you baby to move more freely.

Older toddlers

Called things like ‘Pull-Ups’, 'pull-ons', 'Pull On Pants', 'Easy Up', 'Little Walkers'. Designed to ease the transition from nappy to real pants. Toddlers are often not keen to lie back passively on the changing mat, so pull-ups are great if you need to do a change standing up.


How much does your baby weigh?

Each nappy pack will be labelled with a size and a weight range. The size can also have a name - for example, size 3 is “midi”. The weight range overlaps between sizes, and you’ll find that some of same sizes exist in each range a brand does. Different brands and lines can vary their sizing system. Fit also changes from style to style and brand to brand.

The cost per pack often stays the same between sizes, but the number of nappies per pack reduces as nappies get larger. Check the price per nappy (often found on the price ticket on supermarket shelves) so you get an idea of what you're really spending.

To give you a broad idea of what to expect, here’s how Sainsbury’s sizes work:

  • Size 1 newborn (2-5kg/4-11lb)
  • Size 2 mini (3-6kg/6-13lb)
  • Size 3 midi (4-9kg/9-20lb)
  • Size 4 maxi (7-18kg/15-40lb)
  • Size 4+ maxi + (9-20kg/20-44lb)
  • Size 5 junior (11-25kg/24-55lb)
  • Size 6 extra large (16kg+/35lb+)

Do you want them for day or night use?

When and where you'll be using nappies will probably govern your choices. You don't have to be loyal to one brand or type - it's often handier to mix and match!

You might opt for cheaper disposables in the day when you'll be changing nappies more often, then use a more absorbent, pricier nappy at night, so you don't end up with messy sheets or a baby woken up by wetness.

If your baby’s heading somewhere they’ll be ultra-active – playgroup, baby gym class – you could invest in an ‘active’ style. If a long car journey lies ahead, super-absorbent ‘dry’ nappies might be worth reaching for again.


Where do you start?

Find out which nappies offer the best performance with our in-depth reviews of newborn disposable nappies, disposable nappies for young babies and disposables for older babies. We’ve also put wipes, nappy creams and swimming nappies and pants through their paces.

To save you time and money, we've rounded-up the top-performers, too: