JSON Data Types Last Updated : 11 Jul, 2025 Comments Improve Suggest changes Like Article Like Report JSON (JavaScript Object Notation) is the most widely used data format for data interchange on the web. JSON is a lightweight text-based, data-interchange format and it is completely language-independent.JSON Data Types JSON supports mainly 6 data types: StringNumberBooleanNullObjectArrayNote: string, number, boolean, null are simple data types or primitives data types whereas object and array are referred as complex data types. JSON StringJSON strings must be written in double quotes like C-language there are various special characters(Escape Characters) in JSON that you can use in strings such as \ (backslash), / (forward slash), b (backspace), n (new line), r (carriage return), t (horizontal tab), etc. { "name":"Vivek" }{ "city":"Delhi\/India" }here \/ is used for Escape Character / (forward slash).JSON NumberRepresented in base 10 and octal and hexadecimal formats are not used. { "age": 20 }{ "percentage": 82.44}JSON BooleanThis data type can be either true or false. { "result" : true }JSON NullIt is just a define nullable value. { "result" : true, "grade" : null, "rollno" : 210}JSON ObjectIt is a set of name or value pairs inserted between {} (curly braces). The keys must be strings and should be unique and multiple key and value pairs are separated by a, (comma).{"Geek":{ "name":"Peter", "age":20, "score": 50.05}}JSON ArrayIt is an ordered collection of values and begins with [ (left bracket) and ends with ] (right bracket). The values of array are separated by , (comma).{"geek":[ "Sahil", "Vivek", "Rahul" ]}{ "collection" : [ {"id" : 101}, {"id" : 102}, {"id" : 103} ]} Comment More infoAdvertise with us Next Article Introduction to JavaScript V vivekkothari Follow Improve Article Tags : JavaScript Web Technologies JSON Similar Reads JavaScript Tutorial JavaScript is a programming language used to create dynamic content for websites. It is a lightweight, cross-platform, and single-threaded programming language. 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