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LetterQ[string]

yields True if all the characters in the string are letters, and yields False otherwise.

Details
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Generalizations & Extensions  
Properties & Relations  
Possible Issues  
Neat Examples  
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LetterQ

LetterQ[string]

yields True if all the characters in the string are letters, and yields False otherwise.

Details

  • LetterQ[string] by default gives False if string contains any space or punctuation characters.
  • LetterQ handles both ordinary and special characters.
  • LetterQ treats as letters all special characters explicitly listed as letters in the table in "Named Characters".
  • In general, LetterQ treats as letters all characters that appear as ordinary text in any language.
  • LetterQ treats as letters such special characters as α, , ℒ, and æ.
  • LetterQ does not treat as letters ∅ (\[EmptySet]), ℏ (\[HBar]), Å (\[Angstrom]), or ∑ (\[Sum]).

Examples

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Basic Examples  (1)

Test whether a character is a letter:

Wolfram Language code: LetterQ["a"]
Wolfram Language code: LetterQ["2"]

Scope  (6)

Test whether all characters in a string are letters:

Wolfram Language code: LetterQ["abcdABCD"]

Punctuation is not a letter:

Wolfram Language code: LetterQ["two words"]

Accented letters are still treated as letters:

Wolfram Language code: LetterQ["äé"]

Gothic letters are treated as letters:

Wolfram Language code: LetterQ["𝔄𝔅ℭ𝔇𝔈"]

Greek letters are treated as letters:

Wolfram Language code: LetterQ["αβγδϵζηθ"]

Characters that are not letters in ordinary natural language are not treated as letters:

Wolfram Language code: "∑"
Wolfram Language code: LetterQ[%]

Generalizations & Extensions  (1)

Letters from different character ranges corresponding to different languages:

Wolfram Language code: Style[StringJoin[Select[Characters[FromCharacterCode[Range[1072, 1103]]], LetterQ]], 14]
Wolfram Language code: Style[StringJoin[Select[Characters[FromCharacterCode[Range[2693, 2787]]], LetterQ]], 14]
Wolfram Language code: Style[StringJoin[Select[Characters[FromCharacterCode[Range[2821, 2915]]], LetterQ]], 14]
Wolfram Language code: Style[StringJoin[Select[Characters[FromCharacterCode[Range[3329, 3455]]], LetterQ]], 14]
Wolfram Language code: Style[StringJoin[Select[Characters[FromCharacterCode[Range[11648, 11742]]], LetterQ]], 14]
Wolfram Language code: Style[StringJoin[Select[Characters[FromCharacterCode[Range[12353, 12436]]], LetterQ]], 14]
Wolfram Language code: Style[StringJoin[Select[Characters[FromCharacterCode[Range[12449, 12538]]], LetterQ]], 14]

Properties & Relations  (1)

All characters treated as letters:

Wolfram Language code: Style[StringJoin[Select[Characters[FromCharacterCode[Range[2 ^ 16 - 1]]], LetterQ]], 14]

Possible Issues  (1)

Contiguous characters in character space may not all be letters:

Wolfram Language code: CharacterRange["𝒜", "𝒢"]
Wolfram Language code: LetterQ /@ %

An actual script-B character is nevertheless a letter:

Wolfram Language code: LetterQ["ℬ"]

Neat Examples  (1)

Plot the character codes of letters:

Wolfram Language code: ListPlot[Flatten[ToCharacterCode[Select[Characters[FromCharacterCode[Range[2 ^ 16 - 1]]], LetterQ]]]]

Include the actual names of characters:

Wolfram Language code: With[{u = Select[Characters[FromCharacterCode[Range[1, 2000, 5]]], LetterQ]}, ListPlot[MapIndexed[{{First[#2], First[ToCharacterCode[#1]]}}&, u], PlotMarkers -> u, Frame -> True]]
Wolfram Research (1991), LetterQ, Wolfram Language function, https://reference.wolfram.com/language/ref/LetterQ.html (updated 1996).

Text

Wolfram Research (1991), LetterQ, Wolfram Language function, https://reference.wolfram.com/language/ref/LetterQ.html (updated 1996).

CMS

Wolfram Language. 1991. "LetterQ." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 1996. https://reference.wolfram.com/language/ref/LetterQ.html.

APA

Wolfram Language. (1991). LetterQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/LetterQ.html

BibTeX

@misc{reference.wolfram_2026_letterq, author="Wolfram Research", title="{LetterQ}", year="1996", howpublished="\url{https://reference.wolfram.com/language/ref/LetterQ.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_letterq, organization={Wolfram Research}, title={LetterQ}, year={1996}, url={https://reference.wolfram.com/language/ref/LetterQ.html}, note=[Accessed: 12-June-2026]}