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RealValuedNumberQ[expr]

returns True if expr is a number with a real value and False otherwise.

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RealValuedNumberQ

RealValuedNumberQ[expr]

returns True if expr is a number with a real value and False otherwise.

Details

Examples

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Basic Examples  (1)

Test whether an input is explicitly a real-valued number:

Wolfram Language code: RealValuedNumberQ[(1/2)]
Wolfram Language code: RealValuedNumberQ[x]

Scope  (8)

Integers are real-valued numbers:

Wolfram Language code: RealValuedNumberQ[1]

Rational numbers are real valued:

Wolfram Language code: RealValuedNumberQ[(1/2)]

Approximate reals are real-valued numbers:

Wolfram Language code: RealValuedNumberQ[5.6]
Wolfram Language code: RealValuedNumberQ[5.345`4]

Complex numbers are not real valued:

Wolfram Language code: RealValuedNumberQ[I]

Approximate complex numbers are not considered real valued even if their imaginary part equals zero:

Wolfram Language code: z = 1.2 + 0. I
Wolfram Language code: RealValuedNumberQ[z]
Wolfram Language code: Im[z] == 0

RealValuedNumberQ gives False for expressions that are real valued but not explicitly numbers:

Wolfram Language code: RealValuedNumberQ[π]
Wolfram Language code: RealValuedNumberQ[Sqrt[2]]

RealValuedNumberQ[Infinity] gives False:

Wolfram Language code: RealValuedNumberQ[Infinity]

RealValuedNumberQ[Overflow[]] and RealValuedNumberQ[Underflow[]] give True:

Wolfram Language code: {o, u} = {$MaxNumber * 2, $MinNumber / 2}
Wolfram Language code: {RealValuedNumberQ[o], RealValuedNumberQ[u]}

They are both treated as Real:

Wolfram Language code: {Head[o], Head[u]}

Properties & Relations  (3)

RealValuedNumberQ is effectively equivalent to MatchQ[#,_Integer|_Rational|_Real]&:

Wolfram Language code: realValuedNumberQ = MatchQ[#, _Integer | _Rational | _Real]&;
Wolfram Language code: TableForm[Table[{x, RealValuedNumberQ[x], realValuedNumberQ[x]}, {x, {1, 3 / 2, 1.5, 1 + I, E, Sin[1], Underflow[], Overflow[], Infinity}}], TableHeadings -> {{}, {x, "RealValuedNumberQ", "realValuedNumberQ"}}]

RealValuedNumberQ[x] is equivalent to NumberQ[x]&&Head[x]=!=Complex:

Wolfram Language code: realValuedNumberQ[x_] := NumberQ[x] && Head[x] =!= Complex
Wolfram Language code: TableForm[Table[{x, RealValuedNumberQ[x], realValuedNumberQ[x]}, {x, {1, 3 / 2, 1.5, 1 + I, E, Sin[1], Underflow[], Overflow[], Infinity}}], TableHeadings -> {{}, {x, "RealValuedNumberQ", "realValuedNumberQ"}}]

If RealValuedNumberQ[x] is True, then RealValuedNumericQ[x] is also True:

Wolfram Language code: TableForm[Table[{x, RealValuedNumberQ[x], RealValuedNumericQ[x]}, {x, {1, 3 / 2, 1.5, 1 + I, E, Sin[1], Underflow[], Overflow[], Infinity}}], TableHeadings -> {{}, {x, "RealValuedNumberQ", "RealValuedNumericQ"}}]
Wolfram Research (2023), RealValuedNumberQ, Wolfram Language function, https://reference.wolfram.com/language/ref/RealValuedNumberQ.html.

Text

Wolfram Research (2023), RealValuedNumberQ, Wolfram Language function, https://reference.wolfram.com/language/ref/RealValuedNumberQ.html.

CMS

Wolfram Language. 2023. "RealValuedNumberQ." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/RealValuedNumberQ.html.

APA

Wolfram Language. (2023). RealValuedNumberQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/RealValuedNumberQ.html

BibTeX

@misc{reference.wolfram_2026_realvaluednumberq, author="Wolfram Research", title="{RealValuedNumberQ}", year="2023", howpublished="\url{https://reference.wolfram.com/language/ref/RealValuedNumberQ.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_realvaluednumberq, organization={Wolfram Research}, title={RealValuedNumberQ}, year={2023}, url={https://reference.wolfram.com/language/ref/RealValuedNumberQ.html}, note=[Accessed: 12-June-2026]}