Formatting numbers as currency is essential for e-commerce applications, financial dashboards, pricing components, and shopping cart interfaces in JavaScript. With over 25 years of experience in software development and as the creator of CoreUI, I’ve implemented currency formatting in price displays, checkout forms, and financial tables across our Angular and React component libraries. The modern standard is Intl.NumberFormat — it handles locale-specific symbols, decimal separators, and digit grouping automatically without any manual string manipulation.