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    ISLOGICAL

    Information

    Returns TRUE if the value is a logical value (TRUE or FALSE), FALSE otherwise.

    Translations
    EnglishISLOGICAL
    FrenchESTLOGIQUE
    SpanishESLOGICO
    GermanISTLOG
    ItalianVAL.LOGICO
    PortugueseÉLÓGICO
    DutchISLOGISCH
    PolishCZY.LOGICZNA
    RussianЕЛОГИЧ
    TurkishEMANTIKSALMI
    CzechJE.LOGHODN
    HungarianLOGIKAI
    SwedishÄRLOGISK
    DanishER.LOGISK
    FinnishONTOTUUSARVO
    Syntax
    ISLOGICAL(value)

    Arguments

    • valueThe value you want to test
    Examples
    =ISLOGICAL(TRUE)
    TRUE

    TRUE is a logical value

    =ISLOGICAL(1)
    FALSE

    1 is a number, not a logical value

    =ISLOGICAL(A1>5)
    TRUE

    A comparison returns a logical value

    Tips & Best Practices
    • •Only TRUE and FALSE are considered logical values
    • •Numbers (even 1 and 0) are not logical values
    • •Useful for data validation and error checking
    Common Mistakes
    • •Assuming numbers like 1 and 0 count as logical values because they're sometimes used to represent TRUE and FALSE - ISLOGICAL only recognizes the actual TRUE and FALSE logical type, not numbers that merely resemble them
    • •Using ISLOGICAL to check the result of a comparison and being surprised it works - comparisons like A1>5 genuinely produce a logical value, so this is actually correct behavior, not an edge case
    • •Confusing ISLOGICAL with checking whether a cell's displayed value looks like TRUE or FALSE text - if a cell contains the text string "TRUE" rather than the logical value TRUE, ISLOGICAL returns FALSE
    Related Functions
    ISNUMBERChecks specifically whether a value is a number, a parallel type-check to ISLOGICAL but for a different data type.
    ISTEXTChecks specifically whether a value is text, useful for distinguishing a genuine logical value from a text string that merely looks like one.
    TYPEReturns a numeric code representing a value's type (including logical values as code 4), a broader alternative when you need to distinguish between several possible types at once.
    Frequently Asked Questions

    Does ISLOGICAL count 1 and 0 as logical values?

    No, only the actual TRUE and FALSE logical values are recognized - numbers, even ones commonly used to represent true/false like 1 and 0, return FALSE from ISLOGICAL.

    Why does ISLOGICAL return TRUE for a comparison like A1>5?

    That's expected - comparisons in Excel genuinely evaluate to the logical value TRUE or FALSE, so ISLOGICAL correctly identifies them as logical values.

    Does ISLOGICAL recognize the text "TRUE" as a logical value?

    No, if a cell contains the text string "TRUE" rather than the actual logical value TRUE, ISLOGICAL returns FALSE - text and logical values are different data types in Excel.

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