Digit options

minimumIntegerDigits

The minimum number of integer digits to use. Values with fewer digits are left-padded with zeros to meet the specified length. Valid range: 1 to 21 (default: 1).

Examples:

minimumFractionDigits

The minimum number of fraction digits to display. Valid range: 0 to 100. Defaults: 0 for plain numbers and percentages, or 2 for currencies (based on ISO 4217). See significant and fraction digits default values for details.

Examples:

maximumFractionDigits

The maximum number of fraction digits to use. Valid range: 0 to 100. Defaults:

• Plain numbers: The larger of minimumFractionDigits or 3.
• Currencies: The larger of minimumFractionDigits or the minor unit digits from the ISO 4217 currency code list (2 if unspecified).
• Percentages: The larger of minimumFractionDigits or 0.

See significant and fraction digits default values for details.

Examples:

minimumSignificantDigits

The minimum number of significant digits to use. Possible values are from 1 to 21; the default is 1. See significant and fraction digits default values default values for when this default gets applied.

Examples:

maximumSignificantDigits

The maximum number of significant digits to use. Valid range: 1 to 21 (default: 21). See significant and fraction digits default values for details.

Examples:

roundingPriority

Specify how rounding conflicts are resolved when both fraction digits options (minimumFractionDigits/maximumFractionDigits) and significant digits options (minimumSignificantDigits/maximumSignificantDigits) are set:

• "auto" (default) - Uses the result from significant digits.
• "morePrecision" - Chooses the property yielding more precision.
• "lessPrecision" - Chooses the property yielding less precision.

If notation is "compact" and none of these options are set, "auto" is normalized to "morePrecision".

NOTE

With values other than auto, the result is determined by maximumSignificantDigits and maximumFractionDigits, ignoring minimum digit settings. See default values for details.

Examples:

Formatter options used in this example

{
  minimumSignificantDigits: 3;
  maximumSignificantDigits: 6;
  minimumFractionDigits: 3;
}

roundingIncrement

Defines the step size for rounding, based on the calculated rounding magnitude. Supported values include 1, 2, 5, 10, 20, 25, 50, 100, 200, 250, 500, 1000, 2000, 2500, and 5000. The default is 1. This option is incompatible with significant-digits rounding or any roundingPriority setting other than "auto".

WARNING

This option requires maximumFractionDigits set to 0.

Examples:

Formatter options used in this example

{
  minimumFractionDigits: 0;
}

roundingMode

How decimals are rounded. Possible values:

Rounding mode	Description
"ceil"	Round up (toward +∞).
"floor"	Round down (toward -∞).
"expand"	Round away from 0.
"trunc"	Round toward 0.
"halfCeil"	Ties round up (toward +∞).
"halfFloor"	Ties round down (toward -∞).
"halfExpand"	Ties round away from 0 (default).
"halfTrunc"	Ties round toward 0.
"halfEven"	Ties round to the nearest even number.

Examples:

Formatter options used in this example

{
  maximumSignificantDigits: 1;
}

trailingZeroDisplay

The strategy for displaying trailing zeros on whole numbers:

• "auto" (default): Retains trailing zeros based on minimumFractionDigits and minimumSignificantDigits.
• "stripIfInteger": Removes fraction digits if all are zero; behaves like "auto" if any fraction digit is non-zero.

Examples:

Formatter options used in this example

{
  minimumFractionDigits: 2;
}

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Significant and fraction digits default values

For the four options above, defaults are applied only when the property is used, based on roundingPriority and notation:

• If roundingPriority is not "auto", all four options apply.
• If roundingPriority is "auto" and a significant digits option is set, only significant digits options apply.
• If roundingPriority is "auto" and a fraction digits option is set or notation is not "compact", only fraction digits options apply.
• If roundingPriority is "auto", notation is "compact", and none of the four options are set, they default to { minimumFractionDigits: 0, maximumFractionDigits: 0, minimumSignificantDigits: 1, maximumSignificantDigits: 2 } with roundingPriority set to "morePrecision".

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