Flats Size Conversion Chart

The flats conversion chart

Use the chart below to convert between US, UK and EU flats sizes. Every row is anchored to a foot length range in inches, so the length column is the safest place to start. Find your foot length, read the row, and then take the UK or EU size from that same row. Do not convert from a size number you remember from another brand, because that number may already be off by half a size.

The chart covers US women's 5 to 12, UK 3 to 10 and EU 35.5 to 44.5. These are broad general equivalents for flats, and some brands use slightly different conversions, especially at the half sizes. When a brand chart disagrees with this table, trust the brand chart for that brand, because it describes the actual shoes you are buying.

Conversion table

Each row in the table gives one US women's size, the foot length range that usually fits it, and the matching UK and EU sizes. The US to UK gap is two sizes in this broad general table, so a US 8 is a UK 6. The EU sizes move in half steps, so most US half sizes have their own EU number. Keep the foot length column in view while you convert, because it is the only column that does not change between brands.

Converting US flats sizes to UK sizes

In this broad general table, the UK size is two numbers lower than the US size: US 5 is UK 3, US 7 is UK 5, and US 10 is UK 8. That two size gap holds across the whole table, which makes US to UK conversion simple for flats. Even so, check the brand chart, because a few brands grade their UK sizes half a size differently.

When you shop a brand that lists UK sizes only, measure your foot in inches first and find the row, rather than subtracting two from your usual US size. Your usual US size may come from a brand that grades generously, while the UK brand may grade tightly, and the subtraction would carry the error across. Foot length resets the conversion to a fresh measurement.

Converting US flats sizes to EU sizes

EU flats sizes run from 35.5 to 44.5 in this table, moving in half steps that line up with US half sizes. A US 6 is EU 37, a US 7.5 is EU 38.5, and a US 9 is EU 40.5. The half steps mean that a US half size is not a rounding error in EU sizing; it has its own number, and choosing the wrong one can leave a flat half a size too tight or too loose.

EU conversion is where brands disagree most, because some brands round the EU number up and others round it down. If the brand chart lists an insole length in centimetres, use that instead of the EU number. The insole length tells you how long the inside of the shoe is, which is the measurement that decides whether your foot fits.

Half sizes and sizes outside the chart

Half sizes matter more in flats than in laced shoes, because a flat has no laces to take up the slack. A half size up gives a little extra length and width at the ball, which can be the difference between a pointed toe that pinches and one that fits. If your foot length falls between two rows, read the between sizes guide before you choose, and think about width and toe shape as well as length.

If your foot length falls below US 5 or above US 12, the chart cannot give you a precise conversion. Use the nearest end of the chart as a rough guide and rely on the brand chart and the stated insole length instead. Some brands extend their flats range beyond US 12 or below US 5, and their own charts are the only reliable source for those sizes.

Why converted sizes still differ between brands

A conversion chart describes the general relationship between sizing systems, but each brand grades its own sizes. One brand may cut a US 8 flat a little longer than another, and its UK 6 and EU 39 will follow its own US 8, not the general table. That is why the same foot can be a US 8 in one brand and a US 8.5 in another, and why the converted sizes shift with it.

Toe box shape adds another layer of difference. A pointed flat in EU 39 can feel smaller than a round toe flat in EU 39 from the same brand, because the pointed shape takes room away from the toes. When you convert sizes for a pointed flat, consider going half a size up from the converted number, and check the return policy before you commit.