Joybuy Insights

Buying underwear: how to choose comfortable, well-fitting and practical options

Buying underwear seems simple, until a waistband digs in, fabric starts to pill or briefs show through your clothes. Online, you’ll also come across terms such as “seamless”, “breathable” and “shaping”, but these do not always tell you enough about the fit or care requirements.

This buying guide compares women’s and men’s underwear based on practical criteria. That makes it easier to find cotton underwear, men’s boxers, women’s briefs, women’s thongs, period underwear or comfortable undergarments that suit your everyday needs.

Common pitfalls when buying underwear

1. Looking only at the size on the label

A size M is not the same for every brand. One waistband may fit snugly, while another style is more generous. Always check the size guide for the specific product. For women’s underwear, look at your waist and hip measurements; for men’s underwear, check the stated clothing size or waist measurement.

For example, the Calvin Klein thongs list separate waist and hip measurements. Some men’s boxers mainly use letter sizing. This makes choosing based on just “M” or “L” less reliable.

2. Confusing marketing claims with measurable features

“Seamless” may mean that the edges are barely visible, but it does not necessarily mean that the entire garment is made without seams. “Breathable” also says nothing about the exact fibre composition. So check the material percentage, construction and care instructions.

A cotton blend with elastane can provide comfortable stretch, while modal feels soft against the skin. Synthetic fibres may be needed in women’s shapewear for elasticity, but they sometimes require hand washing. According to the Calvin Klein product description, one particular thong is made from 90% cotton and 10% elastane. That is a more verifiable starting point than a general comfort claim.

3. Buying a multipack without considering how you’ll use it

A 3-pack of underwear is practical if you already know that the fit and style suit you. If you are trying a particular brand or type for the first time, buying a single item may be the wiser choice. Consider the colours too: black, white and grey are easy to coordinate, while light fabrics can sometimes show through white clothing.

For travel or temporary use, disposable underwear can be convenient. Bear in mind the waste, the packaging and the fact that the product is thrown away after being worn once.

What should you look for in terms of material, fit and care?

Material

  • Cotton: generally feels soft and is widely used for everyday underwear.
  • Cotton with elastane: provides extra stretch and helps the style retain its shape.
  • Modal: is known for its smooth, soft feel; always check the exact composition.
  • Nylon and spandex: are often used in women’s shapewear because these materials provide elasticity.
  • Disposable textiles: check whether the product is intended for single use and follow the instructions on the packaging.

A product description containing terms such as “antibacterial” or “moisture-wicking” should be understood as a claim made by the brand or manufacturer. According to the brand’s own research, a particular treatment may support a certain function, but the product information is not a guarantee of an individual experience or medical effect.

Fit

Choose the style based on your clothing and activity:

  • Women’s thongs: minimal visible fabric beneath tight trousers, skirts or dresses.
  • Women’s briefs: more coverage and often suitable for everyday wear.
  • Bikini or mid-rise briefs: a compromise between a low and higher waist.
  • Men’s boxers: more coverage on the legs; trunks usually have shorter legs.
  • Seamless underwear: useful beneath close-fitting clothing, but check exactly where the edges and seams are.
  • Women’s shapewear: designed to create a smoother silhouette under clothing; do not choose a size that feels unnecessarily tight.

Care

Always follow the care label. Many styles can be machine washed, but some shapewear items are suitable for hand washing only. Several Calvin Klein styles recommend washing at a low temperature and advise against tumble drying. Incorrect drying can cause elastane and elastic bands to wear out more quickly.

Suitable for: Budget-conscious beginners
Utree women’s underwear 3-pack

Utree women’s underwear 3-pack

Why it suits this profile: Three colours in one pack are handy for your everyday rotation. Sizes M, L and XL are linked to body height and size guidance; check this before ordering.

How this product avoids the pitfall

The product information specifies the material, stretch and a detailed fit. This allows you to compare more purposefully than by looking only at the colour or marketing name.

Key benefit & highlights

3-pack; modal as the main material according to the product description; high stretch and a style offering more coverage.

Suitable for: Shoppers seeking premium quality
Calvin Klein men’s 3-pack slim boxers

Calvin Klein 3-Pack Slim Boxers - Icon Cotton Stretch

Why it suits this profile: For anyone looking for a recognisable brand, classic colours and a close fit for work and everyday wear.

How this product avoids the pitfall

The composition is described as cotton with elastane, while the fit is listed as slim. However, check the exact label, as the product page does not specify all material percentages.

Key benefit & highlights

3-pack in black, white and grey; slim fit; elasticated waistband and a functional fly without a button, according to the product description.

Suitable for: Specific uses & frequent wearers
C&S Dolemi disposable period underwear

C&S Dolemi disposable period underwear, 8 pieces

Why it suits this profile: Suitable for anyone who does not want to carry laundry during travel, a period or another temporary situation.

How this product avoids the pitfall

The pack contains eight disposable garments and uses side fastenings. This makes the style suitable for temporary, practical use rather than a regular everyday underwear rotation.

Key benefit & highlights

8 pieces per pack; adjustable side tabs; designed for single use and easy removal.

Women’s underwear, men’s underwear or functional undergarments?

For everyday wear, women’s briefs, bikini briefs and cotton underwear are sensible choices if coverage and easy care are important to you. Women’s thongs are better suited to outfits where you want to minimise visible lines. A style such as the Calvin Klein 3-Pack Strings contains three pieces, a cotton blend and minimal coverage. Check the size details carefully: available sizes and measurements may vary from one product to another.

For men, you can choose between trunks and boxers. A relaxed-fit trunk generally offers more room than a slim style. If you are often on the move, look for a flexible waistband and legs that do not ride up easily. Care instructions are just as important as the material.

With women’s shapewear, the choice mainly depends on the level of support you want and the clothes you will wear over it. According to Feelingirl’s product description, the model in question is designed for light shaping and contains nylon and spandex. This does not provide a medical effect; comfort and fit remain personal. If you are unsure, choose a larger size when recommended by the size guide.

Looking for more options?

We’ve put together a complete, up-to-date list of products that fully meet these strict selection criteria and the applicable European safety regulations.

Frequently asked questions about buying underwear

How do I choose the right underwear size?

Measure your waist and hips as indicated in the size guide. Then compare your measurements with the specific brand and style. If you are between sizes, check the fit description and any sizing advice on the product page.

How long does underwear last?

That depends on the material, how often you wear it, detergent, temperature and drying. Elasticated bands can lose their shape more quickly when exposed to high temperatures or tumble drying. Rotate several sets and follow the care label to help maintain the fit for longer.

Is disposable underwear cheaper than regular underwear?

For everyday use, reusable underwear is generally more practical because you can wear it several times. Disposable underwear can be useful for travel, emergencies or situations where washing is difficult. So do not compare only the price per pack; also consider the number of wears and the amount of waste produced.