Quick guide
How to use this calculator
- Enter a finite decimal, fraction, sqrt(integer), or pi.
- Read every containing number set.
- Do not enter a decimal approximation and expect irrationality to be inferred.
Calculation method
Classify only what the notation proves
Finite decimals and integer fractions are rational. A non-square non-negative integer root and pi are irrational. Negative integer roots are non-real complex values.
Worked example
Two square roots
36 is a perfect square, but 44 is not.
√36 = 6 is rational; √44 is irrational
Supported inputs
Precision and limits
Supported grammar
Finite decimal, integer fraction, sqrt(integer), or pi.
No approximation guesses
A finite decimal is rational even when it approximates an irrational constant.