HUANGLUYI

Measure your ring size in 2 minutes with a string, a ring you already own, or your screen. Get US, UK, EU, Japan and China sizes at once, in mm and inches. What's different: it follows ISO 8653:2016, converts both ways, adds a full half-size chart plus guides on temperature and band width, and runs entirely in your browser - no install, no account, nothing uploaded. Free, nine languages, six ring styles.