Even and Odd Checker
This checker determines whether a number is even or odd. A number is even if it is divisible by 2 with no remainder (n % 2 = 0), and odd if it leaves a remainder of 1 when divided by 2 (n % 2 = 1). The concept of even and odd numbers is fundamental in mathematics and has applications in number theory, algebra, and computer science. You can enter a single number or a comma-separated list of numbers to check multiple values at once. The tool displays whether each number is even or odd, and provides summary statistics showing the count of even numbers, the count of odd numbers, the sum of all even numbers, and the sum of all odd numbers in the list.
How to identify even and odd numbers
A number is even if it is divisible by 2 with no remainder. A number is odd if dividing by 2 leaves a remainder of 1. Mathematically:
Even: n % 2 = 0
Odd: n % 2 = 1
Examples of even numbers: 0, 2, 4, 6, 8, 10, 12, 100, 1,000
Examples of odd numbers: 1, 3, 5, 7, 9, 11, 13, 101, 1,001
Even and odd numbers: frequently asked questions
What is an even number?
An even number is an integer that is divisible by 2 with no remainder. Even numbers are 0, 2, 4, 6, 8, 10, 12, and so on. You can check if a number is even by testing whether it divides evenly by 2: if the remainder is 0, it is even.
What is an odd number?
An odd number is an integer that is not divisible by 2. When divided by 2, odd numbers always leave a remainder of 1. Odd numbers are 1, 3, 5, 7, 9, 11, 13, and so on.
How do you check if a number is even or odd?
Use the modulo operation (%). If a number mod 2 equals 0, the number is even. If a number mod 2 equals 1, the number is odd. In a programming context, you can write: 'if (number % 2 === 0) { even } else { odd }'.
Is zero even or odd?
Zero is an even number. Zero divided by 2 equals 0 with no remainder, so it satisfies the definition of an even number. In the modulo operation, 0 % 2 = 0, confirming it is even.
Can negative numbers be even or odd?
Yes, negative numbers can be even or odd using the same rules as positive numbers. For example, -2, -4, -6 are even, and -1, -3, -5 are odd. A negative number is even if it is divisible by 2, and odd otherwise.
Methodology
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.