In this post, we will learn how to check if a number is odd or even in PHP. Before this, let us see what is even and odd number.

What is Even or Odd Number ?

Even : If a number is divisible by 2, then that number is called Even. For example 2, 4, 6, 8... These numbers are divisible by 2.

Odd : If a number is not divisible by 2, then that number is called Odd. For example 1, 3, 5, 7... These numbers are not divisible by 2.

Check If A Number is Even or Odd in PHP

To check if a number is even or odd in PHP, we follow the following code:

<?php
\$n = 4;
if(\$n % 2 == 0) {
echo "Even";
} else {
echo "Odd";
}
?> code-box

Output :
if \$n = 4, then output is Even

if \$n = 5, then output is Odd

Check If A Number is Even or Odd with Form

To check if a number is even or odd with form, we follow the following code. With this help of we can check multiple number dynamically.

<!DOCTYPE html>
<html>
<body>

<?php
if(isset(\$_POST['submit'])){
\$n = \$_POST['number'];
if(\$n % 2 == 0) {
echo "Even";
} else {
echo "Odd";
}
}
?>

<form method="POST">
<input type="number" name="number" required/>
<input type="submit" name="submit" value="Submit"/>
</form>

</body>
</html> code-box

Output :
The output will be received according to the input value.

Get All Even Odd Numbers from a Range

To get all even or odd numbers form a range like 1 to 10, we follow the following code:

<!DOCTYPE html>
<html>
<body>

<?php
// variables for store odd or even numbers
\$even = "";
\$odd = "";
if(isset(\$_POST['submit'])){
\$n = \$_POST['number'];

for(\$i = 1; \$i <= \$n; \$i++) {
if(\$n % 2 == 0) {
\$even.=\$i."," ;
} else {
\$odd.=\$i."," ;
}
}
//remove comma(,) from right side
\$even = rtrim(\$even, ",");
\$odd = rtrim(\$odd, ",");

echo "Even : ".\$even."<br/>";
echo "Odd : ".\$odd;
}

?>

<form method="POST">
<input type="number" name="number" required/>
<input type="submit" name="submit" value="Submit"/>
</form>

</body>
</html> code-box

Output :
if we input 10 then we get output as follows:
Even : 2,4,6,8,10
Odd : 1,3,5,7,9

Summary

In this post we learn how to check if a number is odd or even in PHP. You try to make it yourself. I hope you make. If you face any problem, then comment and tell us. Keep visiting the blog to read more similar posts.