Format a number

Format a number with locale-aware separators, precision, and standard, scientific, engineering, or compact notation.

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ToolNumber Formatter
Input
Output
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Preview

How it works

The finite parsed number is passed to Intl.NumberFormat with the selected locale, decimal precision, and notation. Runtime locale data controls separators, grouping, and digit symbols, so the underlying numeric value is unchanged.

  • en-US, standard notation, and two decimal places form the initial display.
  • Formatting changes presentation only.

Worked example

Format Large Number
Format a large number with commas and 2 decimal places
Input
											1234567.89
Output
												1,234,567.89

When to use this

Finance tables localize grouping, dashboards use compact KPI notation, and engineering reports choose scientific display for scale.

Edge cases

  • The same value can display 1,234.56 or 1.234,56 under different locales.
  • Negative zero may retain a minus sign because it is a distinct IEEE 754 value.
  • Very large or small finite values can round at the requested decimal limit.

References