{"id":364,"date":"2021-03-15T00:56:56","date_gmt":"2021-03-15T00:56:56","guid":{"rendered":"https:\/\/phptutorial.net\/?page_id=364"},"modified":"2025-04-05T14:22:21","modified_gmt":"2025-04-05T14:22:21","slug":"php-float","status":"publish","type":"page","link":"https:\/\/www.phptutorial.net\/php-tutorial\/php-float\/","title":{"rendered":"PHP float"},"content":{"rendered":"\n

Summary<\/strong>: in this tutorial, you’ll learn about floating-point numbers or floats in PHP.<\/p>\n\n\n\n

Introduction to the PHP float #<\/a><\/h2>\n\n\n\n

Floating-point numbers represent numeric values with decimal digits.<\/p>\n\n\n\n

Floating-point numbers are often called floats, doubles, or real numbers. Like integers<\/a>, the range of the floats depends on the platform where PHP runs.<\/p>\n\n\n\n

PHP recognizes floating-point numbers in the following common formats:<\/p>\n\n\n

1.25<\/span>\n3.14<\/span>\n-0.1<\/span><\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
PHP also supports the floating-point numbers in scientific notation:<\/p>\n\n\n
0.125E1<\/span> \/\/ 0.125 * 10^1 or 1.25<\/span><\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
Since PHP 7.4, you can use the underscores in floats to make long numbers more readable. For example:<\/p>\n\n\n
1<\/span>_234_457.89<\/span><\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
Floating-point number accuracy #<\/a><\/h2>\n\n\n\n
Since the computer cannot represent exact floating-point numbers, it can only use approximate representations.<\/p>\n\n\n\n
For example, the result of 0.1 + 0.1 + 0.1 is 0.299999999…, not 0.3. When comparing two floating-point numbers using the == operator, you must be careful.<\/p>\n\n\n\n
The following example returns false<\/code>, which may not be what you expected:<\/p>\n\n\n
<?php<\/span>\n\n$total = 0.1<\/span> + 0.1<\/span> + 0.1<\/span>;\necho<\/span> $total == 0.3<\/span>; \/\/ return false<\/span><\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
Test a float value #<\/a><\/h2>\n\n\n\n
To check if a value is a floating-point number, you use the is_float()<\/code> or is_real()<\/code> function. The is_float()<\/code> returns true<\/code> if its argument is a floating-point number; otherwise, it returns false<\/code>. For example:<\/p>\n\n\n
<?php<\/span>\n\necho<\/span> is_float(0.5<\/span>);<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
Output:<\/p>\n\n\n
1<\/span><\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
Summary #<\/a><\/h2>\n\n\n\n
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  • Floating-point numbers are numbers with decimal points. Floating-point numbers are also known as floats.<\/li>\n\n\n\n
  • PHP can only represent floats approximately, not precisely.<\/li>\n<\/ul>\n
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    Did you find this tutorial useful?<\/div>\n\t\t
    \n\t\t\t\n\t\t\t\t\n\t\t\t\t\t<\/path>\n\t\t\t\t<\/svg>\n\t\t\t\t Yes <\/span>\n\t\t\t<\/button>\n\n\t\t\t\n\t\t\t\t\n\t\t\t\t\t<\/path>\n\t\t\t\t<\/svg>\n\t\t\t\t No <\/span>\n\t\t\t<\/button>\n\t\t<\/div>\n\t<\/header>\n\n\t
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    <\/div>\n\t\t\t\n\t\t\t
Try it<\/a><\/p>\n\n\n\n
Try it<\/a><\/p>\n\n\n\n