The NumberFormatter class

(PHP 5 >= 5.3.0, PHP 7, PHP 8, PECL intl >= 1.0.0)

Introduction

Programs store and operate on numbers using a locale-independent binary representation. When displaying or printing a number it is converted to a locale-specific string. For example, the number 12345.67 is "12,345.67" in the US, "12 345,67" in France and "12.345,67" in Germany.

By invoking the methods provided by the NumberFormatter class, you can format numbers, currencies, and percentages according to the specified or default locale. NumberFormatter is locale-sensitive so you need to create a new NumberFormatter for each locale. NumberFormatter methods format primitive-type numbers, such as double and output the number as a locale-specific string.

For currencies you can use currency format type to create a formatter that returns a string with the formatted number and the appropriate currency sign. Of course, the NumberFormatter class is unaware of exchange rates so, the number output is the same regardless of the specified currency. This means that the same number has different monetary values depending on the currency locale. If the number is 9988776.65 the results will be:

9 988 776,65 € in France
9.988.776,65 € in Germany
$9,988,776.65 in the United States

In order to format percentages, create a locale-specific formatter with percentage format type. With this formatter, a decimal fraction such as 0.75 is displayed as 75%.

For more complex formatting, like spelled-out numbers, the rule-based number formatters are used.

Class synopsis

class NumberFormatter {

/* Constants */

public const int PATTERN_DECIMAL;

public const int DECIMAL;

public const int CURRENCY;

public const int PERCENT;

public const int SCIENTIFIC;

public const int SPELLOUT;

public const int ORDINAL;

public const int DURATION;

public const int PATTERN_RULEBASED;

public const int IGNORE;

public const int CURRENCY_ACCOUNTING;

public const int DEFAULT_STYLE;

public const int ROUND_CEILING;

public const int ROUND_FLOOR;

public const int ROUND_DOWN;

public const int ROUND_UP;

public const int ROUND_HALFEVEN;

public const int ROUND_HALFDOWN;

public const int ROUND_HALFUP;

public const int PAD_BEFORE_PREFIX;

public const int PAD_AFTER_PREFIX;

public const int PAD_BEFORE_SUFFIX;

public const int PAD_AFTER_SUFFIX;

public const int PARSE_INT_ONLY;

public const int GROUPING_USED;

public const int DECIMAL_ALWAYS_SHOWN;

public const int MAX_INTEGER_DIGITS;

public const int MIN_INTEGER_DIGITS;

public const int INTEGER_DIGITS;

public const int MAX_FRACTION_DIGITS;

public const int MIN_FRACTION_DIGITS;

public const int FRACTION_DIGITS;

public const int MULTIPLIER;

public const int GROUPING_SIZE;

public const int ROUNDING_MODE;

public const int ROUNDING_INCREMENT;

public const int FORMAT_WIDTH;

public const int PADDING_POSITION;

public const int SECONDARY_GROUPING_SIZE;

public const int SIGNIFICANT_DIGITS_USED;

public const int MIN_SIGNIFICANT_DIGITS;

public const int MAX_SIGNIFICANT_DIGITS;

public const int LENIENT_PARSE;

public const int POSITIVE_PREFIX;

public const int POSITIVE_SUFFIX;

public const int NEGATIVE_PREFIX;

public const int NEGATIVE_SUFFIX;

public const int PADDING_CHARACTER;

public const int CURRENCY_CODE;

public const int DEFAULT_RULESET;

public const int PUBLIC_RULESETS;

public const int DECIMAL_SEPARATOR_SYMBOL;

public const int GROUPING_SEPARATOR_SYMBOL;

public const int PATTERN_SEPARATOR_SYMBOL;

public const int PERCENT_SYMBOL;

public const int ZERO_DIGIT_SYMBOL;

public const int DIGIT_SYMBOL;

public const int MINUS_SIGN_SYMBOL;

public const int PLUS_SIGN_SYMBOL;

public const int CURRENCY_SYMBOL;

public const int INTL_CURRENCY_SYMBOL;

public const int MONETARY_SEPARATOR_SYMBOL;

public const int EXPONENTIAL_SYMBOL;

public const int PERMILL_SYMBOL;

public const int PAD_ESCAPE_SYMBOL;

public const int INFINITY_SYMBOL;

public const int NAN_SYMBOL;

public const int SIGNIFICANT_DIGIT_SYMBOL;

public const int MONETARY_GROUPING_SEPARATOR_SYMBOL;

public const int TYPE_DEFAULT;

public const int TYPE_INT32;

public const int TYPE_INT64;

public const int TYPE_DOUBLE;

public const int TYPE_CURRENCY;

/* Methods */

public __construct(string $locale, int $style, ?string $pattern = null)

public static create(string $locale, int $style, ?string $pattern = null): ?NumberFormatter

public formatCurrency(float $amount, string $currency): string|false

public format(int|float $num, int $type = NumberFormatter::TYPE_DEFAULT): string|false

public getAttribute(int $attribute): int|float|false

public getErrorCode(): int

public getErrorMessage(): string

public getLocale(int $type = ULOC_ACTUAL_LOCALE): string|false

public getPattern(): string|false

public getSymbol(int $symbol): string|false

public getTextAttribute(int $attribute): string|false

public parseCurrency(string $string, string &$currency, int &$offset = null): float|false

public parse(string $string, int $type = NumberFormatter::TYPE_DOUBLE, int &$offset = null): int|float|false

public setAttribute(int $attribute, int|float $value): bool

public setPattern(string $pattern): bool

public setSymbol(int $symbol, string $value): bool

public setTextAttribute(int $attribute, string $value): bool

}

Predefined Constants

Format Types

These styles are used by the numfmt_create() to define the type of the formatter.

NumberFormatter::PATTERN_DECIMAL: Decimal format defined by pattern
NumberFormatter::DECIMAL: Decimal format
NumberFormatter::CURRENCY: Currency format
NumberFormatter::PERCENT: Percent format
NumberFormatter::SCIENTIFIC: Scientific format
NumberFormatter::SPELLOUT: Spellout rule-based format
NumberFormatter::ORDINAL: Ordinal rule-based format
NumberFormatter::DURATION: Duration rule-based format
NumberFormatter::PATTERN_RULEBASED: Rule-based format defined by pattern
NumberFormatter::CURRENCY_ACCOUNTING: Currency format for accounting, e.g., ($3.00) for negative currency amount instead of -$3.00. Available as of PHP 7.4.1 and ICU 53.
NumberFormatter::DEFAULT_STYLE: Default format for the locale
NumberFormatter::IGNORE: Alias for PATTERN_DECIMAL

Number Format Specifiers

These constants define how the numbers are parsed or formatted. They should be used as arguments to numfmt_format() and numfmt_parse().

NumberFormatter::TYPE_DEFAULT: Derive the type from variable type
NumberFormatter::TYPE_INT32: Format/parse as 32-bit integer
NumberFormatter::TYPE_INT64: Format/parse as 64-bit integer
NumberFormatter::TYPE_DOUBLE: Format/parse as floating point value
NumberFormatter::TYPE_CURRENCY: Format/parse as currency value. Deprecated as of PHP 8.3.0

Number Format Attributes

Number format attribute used by numfmt_get_attribute() and numfmt_set_attribute().

NumberFormatter::PARSE_INT_ONLY: Parse integers only.
NumberFormatter::GROUPING_USED: Use grouping separator.
NumberFormatter::DECIMAL_ALWAYS_SHOWN: Always show decimal point.
NumberFormatter::MAX_INTEGER_DIGITS: Maximum integer digits.
NumberFormatter::MIN_INTEGER_DIGITS: Minimum integer digits.
NumberFormatter::INTEGER_DIGITS: Integer digits.
NumberFormatter::MAX_FRACTION_DIGITS: Maximum fraction digits.
NumberFormatter::MIN_FRACTION_DIGITS: Minimum fraction digits.
NumberFormatter::FRACTION_DIGITS: Fraction digits.
NumberFormatter::MULTIPLIER: Multiplier.
NumberFormatter::GROUPING_SIZE: Grouping size.
NumberFormatter::ROUNDING_MODE: Rounding Mode.
NumberFormatter::ROUNDING_INCREMENT: Rounding increment.
NumberFormatter::FORMAT_WIDTH: The width to which the output of format() is padded.
NumberFormatter::PADDING_POSITION: The position at which padding will take place. See pad position constants for possible argument values.
NumberFormatter::SECONDARY_GROUPING_SIZE: Secondary grouping size.
NumberFormatter::SIGNIFICANT_DIGITS_USED: Use significant digits.
NumberFormatter::MIN_SIGNIFICANT_DIGITS: Minimum significant digits.
NumberFormatter::MAX_SIGNIFICANT_DIGITS: Maximum significant digits.
NumberFormatter::LENIENT_PARSE: Lenient parse mode used by rule-based formats.

Number Format Text Attributes

Number format text attribute used by numfmt_get_text_attribute() and numfmt_set_text_attribute().

NumberFormatter::POSITIVE_PREFIX: Positive prefix.
NumberFormatter::POSITIVE_SUFFIX: Positive suffix.
NumberFormatter::NEGATIVE_PREFIX: Negative prefix.
NumberFormatter::NEGATIVE_SUFFIX: Negative suffix.
NumberFormatter::PADDING_CHARACTER: The character used to pad to the format width.
NumberFormatter::CURRENCY_CODE: The ISO currency code.
NumberFormatter::DEFAULT_RULESET: The default rule set. This is only available with rule-based formatters.
NumberFormatter::PUBLIC_RULESETS: The public rule sets. This is only available with rule-based formatters. This is a read-only attribute. The public rulesets are returned as a single string, with each ruleset name delimited by ';' (semicolon).

Symbol Format Specifiers

Number format symbols used by numfmt_get_symbol() and numfmt_set_symbol().

NumberFormatter::DECIMAL_SEPARATOR_SYMBOL: The decimal separator.
NumberFormatter::GROUPING_SEPARATOR_SYMBOL: The grouping separator.
NumberFormatter::PATTERN_SEPARATOR_SYMBOL: The pattern separator.
NumberFormatter::PERCENT_SYMBOL: The percent sign.
NumberFormatter::ZERO_DIGIT_SYMBOL: Zero.
NumberFormatter::DIGIT_SYMBOL: Character representing a digit in the pattern.
NumberFormatter::MINUS_SIGN_SYMBOL: The minus sign.
NumberFormatter::PLUS_SIGN_SYMBOL: The plus sign.
NumberFormatter::CURRENCY_SYMBOL: The currency symbol.
NumberFormatter::INTL_CURRENCY_SYMBOL: The international currency symbol.
NumberFormatter::MONETARY_SEPARATOR_SYMBOL: The monetary separator.
NumberFormatter::EXPONENTIAL_SYMBOL: The exponential symbol.
NumberFormatter::PERMILL_SYMBOL: Per mill symbol.
NumberFormatter::PAD_ESCAPE_SYMBOL: Escape padding character.
NumberFormatter::INFINITY_SYMBOL: Infinity symbol.
NumberFormatter::NAN_SYMBOL: Not-a-number symbol.
NumberFormatter::SIGNIFICANT_DIGIT_SYMBOL: Significant digit symbol.
NumberFormatter::MONETARY_GROUPING_SEPARATOR_SYMBOL: The monetary grouping separator.

Rounding Modes

Rounding mode values used by numfmt_get_attribute() and numfmt_set_attribute() with NumberFormatter::ROUNDING_MODE attribute.

NumberFormatter::ROUND_CEILING: Rounding mode to round towards positive infinity.
NumberFormatter::ROUND_DOWN: Rounding mode to round towards zero.
NumberFormatter::ROUND_FLOOR: Rounding mode to round towards negative infinity.
NumberFormatter::ROUND_HALFDOWN: Rounding mode to round towards "nearest neighbor" unless both neighbors are equidistant, in which case round down.
NumberFormatter::ROUND_HALFEVEN: Rounding mode to round towards the "nearest neighbor" unless both neighbors are equidistant, in which case, round towards the even neighbor.
NumberFormatter::ROUND_HALFUP: Rounding mode to round towards "nearest neighbor" unless both neighbors are equidistant, in which case round up.
NumberFormatter::ROUND_UP: Rounding mode to round away from zero.

Padding Specifiers

Pad position values used by numfmt_get_attribute() and numfmt_set_attribute() with NumberFormatter::PADDING_POSITION attribute.

NumberFormatter::PAD_AFTER_PREFIX: Pad characters inserted after the prefix.
NumberFormatter::PAD_AFTER_SUFFIX: Pad characters inserted after the suffix.
NumberFormatter::PAD_BEFORE_PREFIX: Pad characters inserted before the prefix.
NumberFormatter::PAD_BEFORE_SUFFIX: Pad characters inserted before the suffix.