About SizeCharts

Why this exists

Every jewelry brand, shoe maker and clothing label publishes its own size guide, and each one only shows its own products in its own home market. If you are buying across borders or comparing brands, that leaves you stitching together half a dozen incompatible charts. SizeCharts solves that by being neutral: one set of tables that maps US, UK, EU and international sizes to the physical measurement underneath, so any label can be read against any other.

How the tables are built

Every conversion is anchored to a real physical dimension. Ring sizes come from the inside diameter and circumference of the band in millimetres. Shoe sizes come from foot length in centimetres. Hat sizes come from head circumference, bra sizes from underbust and bust, and clothing from chest, bust and waist. Because the labels all describe the same measurement, the conversions are exact rather than approximate, and we cross-check them against published international sizing standards.

How it stays accurate

Each data page carries a last-updated date, and the changelog records what changed and when. Sizing standards move slowly, but brand conventions drift, so we keep the note honest: the charts are a reliable starting point, and you should always confirm a specific brand fit before you buy.

Free, private, no tracking

There is no sign up, no paywall and no advertising. Every converter runs in your browser using static tables built into the page, so nothing you type is sent anywhere. For developers, the same data is available as a free JSON API, and the converter can be embedded on any site.