Intl.NumberFormat Playground

Test JavaScript's Intl.NumberFormat with live locale, style, and digit options. Compare the same value across many locales, inspect each formatted token via formatToParts, and copy a ready-to-use options object.

Number

Locale

Options

Style

Currency

Currency Display

Currency Sign

Unit

Unit Display

Notation

Sign Display

Grouping

Numbering System

Min Integer Digits

Min Fraction Digits

Max Fraction Digits

Min Significant Digits

Max Significant Digits

Rounding Mode

Formatted Output

—

Options object

{}

Side-by-side across locales

Same value, same options, 15 representative locales.

Locale	Formatted

About

Intl.NumberFormat is the browser's built-in locale-aware number formatter — the same engine that powers toLocaleString(). It handles digit grouping, currency symbols, percent signs, scientific and compact notation, and numbering systems beyond Latin digits, all without shipping a kilobyte of code. The options here mirror the spec: pick a style (decimal, currency, percent, unit), a notation (standard, scientific, engineering, compact), and constrain fraction or significant digits. Rounding modes match the IEEE 754 catalog. Output runs entirely in your browser's ICU data — nothing leaves the page.