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ExactNumberQ[expr]

returns True if expr is an exact real or complex number, and returns False otherwise.

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ExactNumberQ

ExactNumberQ[expr]

returns True if expr is an exact real or complex number, and returns False otherwise.

Details

Examples

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Basic Examples  (1)

ExactNumberQ tests whether an object is explicitly an exact number:

Scope  (2)

Both real and imaginary parts of a complex number must be exact:

ExactNumberQ is false for symbolic objects that represent numbers:

You can test these with NumericQ:

Properties & Relations  (4)

Numbers are considered either exact or approximate (inexact):

Exact numbers have Precision :

Exact numbers have Head Integer, Rational, or Complex:

A function equivalent to ExactNumberQ:

Wolfram Research (1999), ExactNumberQ, Wolfram Language function, https://reference.wolfram.com/language/ref/ExactNumberQ.html.

Text

Wolfram Research (1999), ExactNumberQ, Wolfram Language function, https://reference.wolfram.com/language/ref/ExactNumberQ.html.

CMS

Wolfram Language. 1999. "ExactNumberQ." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/ExactNumberQ.html.

APA

Wolfram Language. (1999). ExactNumberQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ExactNumberQ.html

BibTeX

@misc{reference.wolfram_2025_exactnumberq, author="Wolfram Research", title="{ExactNumberQ}", year="1999", howpublished="\url{https://reference.wolfram.com/language/ref/ExactNumberQ.html}", note=[Accessed: 28-August-2025]}

BibLaTeX

@online{reference.wolfram_2025_exactnumberq, organization={Wolfram Research}, title={ExactNumberQ}, year={1999}, url={https://reference.wolfram.com/language/ref/ExactNumberQ.html}, note=[Accessed: 28-August-2025]}