Japan

ISO country codes are the connective tissue behind global software. The alpha-2 code is the most common identifier used in APIs, databases, and analytics pipelines because it is compact, stable, and broadly recognized across vendors. Alpha-3 codes provide a more human-friendly option when clarity matters in reports or exports, while numeric ISO codes can be useful in systems that prefer digits-only identifiers. Together, they create a reliable way to represent a country without ambiguity, even when names vary across languages and contexts.

International calling codes serve a different but equally important purpose: they define how telephone numbers are dialed across borders under the E.164 numbering standard. Product teams often need both code families at the same time. A signup form might store the alpha-2 code for address normalization, while a messaging service uses the calling code to validate phone numbers and route communications correctly. By keeping ISO identifiers, dialing prefixes, and currency references side by side, this page helps you design systems that are both accurate and interoperable at global scale.