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<chrconvert_cyr_string>
^String FunctionsLast updated: Mon, 26 Oct 2026

chunk_split

(PHP 4, PHP 5, PHP 7, PHP 8)

chunk_split — Split a string into smaller chunks

Description

function chunk_split(string $string, int $length = 76, string $separator = "\r\n"): string

Can be used to split a string into smaller chunks which is useful for e.g. converting base64_encode() output to match RFC 2045 semantics. It inserts separator every length characters.

Parameters

string

The string to be chunked.

length

The chunk length.

separator

The line ending sequence.

Return Values

Returns the chunked string.

Errors/Exceptions

Throws a ValueError if length is less than 1.

Changelog

Version Description
8.0.0 Now throws a ValueError if length is less than 1. Previously, an E_WARNING was raised and false was returned.

Examples

Example #1 chunk_split() example

<?php
$data = 'This is quite a long string, which will get broken up because the line is going to be too long after base64 encoding it.';

// format $data using RFC 2045 semantics
$new_string = chunk_split(base64_encode($data));
echo $new_string, PHP_EOL;
?>

See Also


<chrconvert_cyr_string>
^String FunctionsLast updated: Mon, 26 Oct 2026