What Is the Difference Between A Rational Number and An Irrational Number?

Learn to tell the difference between rational and irrational numbers.

Jason Marshall, PhD
1-minute read


Rational numbers are all the numbers that can be written like fractions with one integer (the numerator) over another integer (the denominator). This includes all the normal fractions that you’re familiar with—such as 1/2, 3/7, and so on—as well as all the integers. Why the integers? Because they can be written like fractions too. For example, the integer 5 can also be written 5/1. Irrational numbers, on the other hand, are all the numbers that cannot be written this way.
For more, see What are Rational Numbers?



About the Author

Jason Marshall, PhD

Jason Marshall is the author of The Math Dude's Quick and Dirty Guide to Algebra. He provides clear explanations of math terms and principles, and his simple tricks for solving basic algebra problems will have even the most math-phobic person looking forward to working out whatever math problem comes their way.