PHP 4, PHP 5, PHP 7, PHP 8
base_convert - Convert a number between arbitrary bases

base_convert( string$num, int$from_base, int$to_base ): string

Returns a string containing num represented in base to_base. The base in which num is given is specified in from_base. Both from_base and to_base have to be between 2 and 36, inclusive. Digits in numbers with a base higher than 10 will be represented with the letters a-z, with a meaning 10, b meaning 11 and z meaning 35. The case of the letters doesn't matter, i.e. num is interpreted case-insensitively.


base_convert may lose precision on large numbers due to properties related to the internal "double" or "float" type used. Please see the Floating point numbers section in the manual for more specific information and limitations.



The number to convert. Any invalid characters in num are silently ignored. As of PHP 7.4.0 supplying any invalid characters is deprecated.


The base num is in


The base to convert num to

Return Values

num converted to base to_base


Version Description
7.4.0 Passing invalid characters will now generate a deprecation notice. The result will still be computed as if the invalid characters did not exist.

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Function base_convert:

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