Flag Icons

Flag Icons is a comprehensive, carefully maintained collection of all country and territory flags in SVG format, created by Panayiotis Lipiridis. Each flag is available in two aspect ratios: the standard 4x3 rectangular format and a 1x1 square version, making the set flexible for any UI layout. All flags follow ISO 3166-1-alpha-2 country codes and are named accordingly (e.g., us.svg, de.svg, jp.svg), making integration straightforward. The collection covers all 195 UN-recognized countries plus dozens of territories, dependencies, and special regions such as the EU flag, ASEAN, and sub-national flags. Flag Icons also ships with a CSS helper file and full Sass support, allowing you to display flags with simple class names like .fi.fi-us. With over 11,800 stars on GitHub and active maintenance, it is the most popular open-source flag icon library available.