How to Choose the Right Shoe Size Online | Fuix Guides

When you buy shoes online, choosing the right size is one of the most important decisions before placing an order. Unlike shopping in a physical store, you can't try the shoe on before it arrives. Knowing your foot measurement, understanding international sizing systems, and reading the product description carefully helps reduce the risk of receiving a shoe that doesn't fit.

This Fuix guide covers the key criteria for choosing the right shoe size when shopping online — with practical advice on how to measure your foot, how to read size conversion charts, and what to do when you're between sizes.

At a glance

Contents

1. Why size matters more when shopping online
2. How to measure your foot at home
3. EU, UK and US size charts
4. Sneaker sizing
5. Running shoe sizing
6. What to do if you're between sizes
7. Materials, fit and use
8. Pre-purchase checklist

1. Why size matters more when shopping online

In a physical store, you try the shoe on before buying. Online, you rely on the product description, your own measurements, and any fit notes provided.

Getting the size wrong can lead to:

• discomfort during use;
• pressure on the foot or toes;
• instability when walking;
• having to request a return or exchange.

Starting with the right size makes the purchase more straightforward. It's worth taking a few extra minutes before placing your order.

2. How to measure your foot at home

The starting point for finding the right size is knowing the length of your foot in centimetres. You can measure it easily at home:

1. place a sheet of paper on a flat, hard surface;
2. stand on the paper with your full weight on the foot;
3. trace the outline of your foot with a pencil held vertically;
4. measure the distance from the heel to the tip of the longest toe (usually the big toe);
5. repeat for the other foot and use the larger measurement.

The best time to measure is at the end of the day, when your foot is slightly larger from daily use. This gives you the most realistic measurement for a shoe that stays comfortable after hours of wear.

If possible, also measure the width of your foot at its widest point. If you have wider feet, you may need a larger size or a model available in a wide fit.

3. EU, UK and US size charts

The three most common sizing systems are EU (European), UK (British) and US (American). Conversions between these systems are approximate: not all brands use the same correspondences, and fit can vary even within the same brand.

The following table is only an indicative example to show how size conversions may be presented across different systems. It does not replace the official brand size chart or the information provided in the product description.

Note: the values above are indicative and do not represent an official conversion valid for all brands. The exact correspondence varies by brand, model, gender and shoe type. Always verify the size in the product description.

4. Sneaker sizing: what to consider

Sneakers are among the most popular shoes to buy online. A few things to keep in mind when choosing your size:

• Upper shape: a narrower or more tapered upper can make a shoe feel smaller than its stated size;
• Padding: more heavily padded sneakers may feel more enclosed around the foot;
• Material: technical fabric or mesh uppers tend to adapt better to the foot than stiff synthetic leather;
• Everyday use: for sneakers you'll wear for long periods, a slightly roomier fit is often more comfortable over time.

If you're unfamiliar with how a specific brand fits, look for fit notes in the product description or any guidance on whether the model runs large, small, or true to size.

5. Running shoe sizing

Running shoes are built differently from lifestyle sneakers. A few specific considerations:

• Toe room: during a run, the foot slides slightly forward. For this reason, running shoes are often sized up by half a size or a full size compared to your normal size;
• Drop and cushioning: these affect how the foot lands, but don't change the length you need;
• Width options: many brands offer running shoes in standard and wide (W) widths. If you have wider feet, check whether a wide option is available for the model you're considering;
• Sock thickness: technical running socks tend to be thicker than casual socks, which may require sizing up by half a size compared to everyday footwear.

6. What to do if you're between sizes

This is a common situation. If your foot measurement falls between two sizes, these factors can help you decide:

If in doubt, check the seller's return policy before purchasing. Knowing you can return the shoes if they don't fit reduces the risk of an incorrect order. See the Shipping and returns page for the conditions that apply on Fuix.

7. Materials, fit and use

Beyond foot length, several other factors affect how a shoe fits:

• Upper material: fabric or mesh uppers adapt better to the shape of the foot than stiff synthetic materials;
• Sole and drop: a thicker sole provides more cushioning but can make a shoe feel more enclosed;
• Removable insole: some shoes have a removable insole that can be replaced with a custom orthotic — in that case, you may need to go up a size to accommodate it;
• Closure type: adjustable laces allow for a more customised fit than fixed velcro or zip closures.

To understand the specific characteristics of a model, read the product description carefully, including any fit notes. On Fuix you'll find a selection of shoes from selected brands, with information designed to help you choose with more confidence.

8. Pre-purchase checklist

Before confirming your order, run through these points:

• Do I know the length of my foot in centimetres?
• Have I compared my measurement with the size listed in the product description?
• Have I read any fit notes for this specific model?
• Have I considered the type of socks I'll be wearing?
• If I'm between sizes, have I factored in the shoe type and intended use?
• Have I checked the return policy in case the size doesn't fit?
• Have I reviewed the information on authenticity, returns and purchase conditions?

For more information on shipping, returns and purchase conditions, visit the Shipping and returns page and the FAQ. For details on the products available on Fuix, visit our Original products and authenticity page.

FAQ

How do I find my EU shoe size?

Measure the length of your foot in centimetres (from the heel to the tip of the longest toe) and compare it with an EU size chart. Keep in mind that these charts are approximate and fit can vary between brands and models.

Is EU sizing the same across all brands?

Not necessarily. EU sizing is a common reference, but fit varies from brand to brand and between models. Always read the product notes and fit guidance for the specific model you're considering.

Should I size up for running shoes?

Often yes. During a run, the foot slides slightly forward, so having a little extra room at the toe is helpful. Many runners choose a half size or full size up from their everyday shoe size. Check the brand's and model's specific guidance.

What if the size doesn't fit when the shoes arrive?

Check the seller's return policy before purchasing. On Fuix, return conditions are outlined on the Shipping and returns page.

I have wide feet — how should I choose my size?

If you have wider feet, consider going up a size from your standard measurement, or look for models available in a wide-fit (W) option. Avoid shoes with very narrow or tapered uppers.

Conclusion

Choosing the right shoe size when shopping online takes a little more care than buying in a store. Measuring your foot, reading the product description, and checking the return policy are the three key steps to reduce the risk of ordering the wrong size.

On Fuix you'll find a selection of sneakers, shoes and running shoes from selected brands, with product information designed to help you shop online with more confidence. You may also find our guide How to Choose the Right Everyday Sneakers useful for further advice.