Not just size: Why instep, width and more are crucial when buying shoes

Many people know their shoe size—but hardly anyone knows their instep. Yet this very measurement can determine whether a shoe feels comfortable or becomes torture after an hour. If you know your foot shape, you’ll benefit from paying attention to more than just size when buying shoes.

At GIESSWEIN, we know every foot is unique. That’s why we design our shoes with a special focus on comfort and fit. In addition to the right shoe size, instep height, shoe width, and ball width play a decisive role. Many of our models are therefore available in different widths—for a comfortable feel from the very first step.

The most important foot measurements at a glance

Length
Is the most familiar measurement—the basis of every shoe size. But on its own, it often isn’t enough.

Instep (instep height)

Refers to the height of the top of the foot—the arched area between toes and ankle. A high instep means the foot needs more room on top, while a low instep (sometimes associated with flat feet or a low arch) leaves too much space in many shoes and can reduce support.

Shoe width

Shoe width describes the girth of the foot at the ball and complements shoe size for an optimal fit.

At GIESSWEIN, we distinguish three widths:

• Width F - for narrow to regular feet

• Width G - for regular feet with average width

• Width H - for slightly wider, fuller feet

With the right width, wearing comfort can be significantly improved and pressure points can be avoided.

Ball width

Is the absolute width of the foot at its widest point. This measurement is especially important for those with a splayed forefoot.

For which feet are these measurements especially important?

1. High arch / High instep (cavus foot) --> People with a pronounced arch often have a high instep. Standard lace-ups or slip-ons can then press over the instep or fail to close completely. If you know your instep height, you can choose models that offer enough room over the top of the foot.
   GIESSWEIN RECOMMENDATION: Merino Runners + Wool Peak + Wool Trail X

2. Low instep (flat foot) --> With a low instep, shoes often fit too loosely over the top and lose hold. Lace-up styles help, as they can be adjusted individually to the foot for a secure fit.
   GIESSWEIN RECOMMENDATION: Wool Sneaker + Merino Runners + Merino Wool Knit

3. Wide forefoot / Splayed forefoot --> The transverse arch has dropped, and the forefoot spreads out. If you only shop by shoe size, you’ll often end up with shoes that are too tight. Ball width and shoe width are crucial here to avoid pressure points and give your toes enough space. For slightly fuller feet, we recommend our models in Width H.
   GIESSWEIN RECOMMENDATION: Merino Runners + Wool Sneaker + Merino Curve Max

4. Tendency to swell / Water retention --> If your feet tend to swell—due to standing for long periods, pregnancy, or medical conditions—measure your width in the evening, when your foot is at its widest. Shoes with laces or hook-and-loop straps can be adjusted throughout the day.
   GIESSWEIN RECOMMENDATION: Merino Runners + Wool Peak + Merino Easy Step

How to measure your instep and width

A simple at-home method:

1. Stand on a white sheet of paper.

2. Trace your foot while holding the pen vertically.

3. Measure the foot length from heel to the longest toe.

4. Determine the ball width at the widest part of the forefoot.

5. Using a tape measure, measure the circumference over the highest point on the top of the foot—this is the instep.

With these measurements, it becomes much easier to find the right shoe size and width.

Shoe size is just one part of the perfect fit. If you also consider instep height, shoe width, and ball width, you’ll find shoes that fit optimally and provide long-term comfort.

At GIESSWEIN, many models are available in Width F, G, and H. This way, narrow to regular, average-width, and slightly fuller feet can find the right fit. Combined with high-quality materials like Merino wool, this creates an especially comfortable wearing experience—for everyday life, travel, or long walks.