Locale Number Formatter
Format numbers for any locale using the Intl.NumberFormat API.
1,234,567.89
Same number across locales
| en-US | English (United States) | 1,234,567.89 |
| en-GB | English (United Kingdom) | 1,234,567.89 |
| de-DE | German (Germany) | 1.234.567,89 |
| fr-FR | French (France) | 1 234 567,89 |
| es-ES | Spanish (Spain) | 1.234.567,89 |
| it-IT | Italian (Italy) | 1.234.567,89 |
| pt-BR | Portuguese (Brazil) | 1.234.567,89 |
| ja-JP | Japanese (Japan) | 1,234,567.89 |
Intl.NumberFormat — internationalising numbers
Intl.NumberFormatis a built-in browser and Node.js API for locale-aware number formatting. It handles decimal separators (1,234.56 in en-US vs 1.234,56 in de-DE), currency symbols ($1,234.56 vs €1.234,56), percentage notation, and unit labelling. This tool uses the same API your users' browsers use, so what you preview here is exactly what they'll see. All formatting runs in your browser — no data leaves your device.
Private & free — this tool runs entirely in your browser.
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