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Which of these is NOT one of JSON's built-in value types?

Date. JSON has strings, numbers, booleans, null, objects and arrays only.

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  1. null
  2. boolean
  3. date ✔

Why: JSON has four simple types (string, number, boolean, null) and two containers (object and array). There is no date type, so dates are usually sent as strings such as 2026-10-10.

Huh, didn't know that: RFC 8259 defines JSON as a text format that is independent of programming language.

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JSON can't go on dates. It just turns them into strings.
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References

Answer: date. JSON has four simple types (string, number, boolean, null) and two containers (object and array). There is no date type, so dates are usually sent as strings such as 2026-10-10.

  1. RFC 8259: The JavaScript Object Notation (JSON) Data Interchange Format www.rfc-editor.org/rfc/rfc8259
    JSON can represent four primitive types (strings, numbers, booleans, and null) and two structured types (objects and arrays).
    Checked 2026-10-10.

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