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MissingQ[expr]

gives True if expr has head Missing.

Examples  
Basic Examples  
Properties & Relations  
Possible Issues  
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MissingQ

MissingQ[expr]

gives True if expr has head Missing.

Examples

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Basic Examples  (1)

Test whether an expression has head Missing:

Wolfram Language code: MissingQ[5]
Wolfram Language code: MissingQ[Missing["NotAvailable"]]

Properties & Relations  (2)

Selecting values for which MissingQ gives False is equivalent to DeleteMissing:

Wolfram Language code: x = {1, 2, 3, Missing[], 4, 5, 6};
Wolfram Language code: Select[x, MissingQ[#] == False&]
Wolfram Language code: DeleteMissing[x]

Keys not present in an association will return Missing["KeyAbsent",…]:

Wolfram Language code: assoc = <|a -> 1, b -> 2|>
Wolfram Language code: assoc[c]

Use MissingQ to detect such results:

Wolfram Language code: MissingQ[assoc[c]]

Possible Issues  (1)

MissingQ does not yield True for the symbol Missing itself:

Wolfram Language code: MissingQ[Missing]
Wolfram Language code: MissingQ[Missing[]]
Wolfram Research (2015), MissingQ, Wolfram Language function, https://reference.wolfram.com/language/ref/MissingQ.html.

Text

Wolfram Research (2015), MissingQ, Wolfram Language function, https://reference.wolfram.com/language/ref/MissingQ.html.

CMS

Wolfram Language. 2015. "MissingQ." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/MissingQ.html.

APA

Wolfram Language. (2015). MissingQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/MissingQ.html

BibTeX

@misc{reference.wolfram_2026_missingq, author="Wolfram Research", title="{MissingQ}", year="2015", howpublished="\url{https://reference.wolfram.com/language/ref/MissingQ.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_missingq, organization={Wolfram Research}, title={MissingQ}, year={2015}, url={https://reference.wolfram.com/language/ref/MissingQ.html}, note=[Accessed: 12-June-2026]}