$re = '/(?x) # free-spacing mode
(?(DEFINE)
# decimal to decimal: 1.2% to 21.53%
(?<dec_to_dec>
(?:[0-9]{1,3}[\,\.][0-9]{1,3}[\%]\sto\s[0-9]{1,3}[\,\.][0-9]{1,3}[\%])
)
# Decimal to Whole number: 1.2% to 21%
(?<dec_to_int>
(?:[0-9]{1,3}[\,\.][0-9]{1,3}[\%]\sto\s[0-9]{1,3}[\%])
)
# Whole number to Decimal: 1% to 21.53%
(?<int_to_dec>
(?:[0-9]{1,3}[\%]\sto\s[0-9]{1,3}[\,\.][0-9]{1,3}[\%])
)
# Whole number to whole number: 1% to 21%
(?<int_to_int>
(?:[0-9]{1,3}[\%]\sto\s[0-9]{1,3}[\%])
)
# Single Whole Number: 21%
(?<single_int>
(?:[0-9]{1,3}[\%])
)
# Single Whole Number: 21%
(?<single_dec>
(?:[0-9]{1,3}[\,\.][0-9]{1,3}[\%])
)
)
(?&dec_to_dec)|(?&dec_to_int)|(?&int_to_dec)|(?&int_to_int)|(?&single_int)|(?&single_dec)/m';
$str = 'France: 2.8% to 21%';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php