How to Get a Variable Type in TypeScript Last Updated : 18 Jul, 2024 Comments Improve Suggest changes Like Article Like Report Understanding how to effectively ascertain the type of a variable in TypeScript is important for maintaining type safety and ensuring code robustness. In this article, we'll explore various approaches to determine the type of a variable, ranging from basic JavaScript operators to TypeScript-specific features like type guards.Below are the approaches used to get a variable type in TypeScript:Table of ContentApproach 1: Using typeof OperatorApproach 2: Using instanceof OperatorApproach 3: Using Type GuardsApproach 1: Using typeof OperatorThe typeof operator is a straightforward JavaScript feature that TypeScript also utilizes. It returns a string indicating the data type of its operand.Example: In this example, we are using typeof Operator to get the type of a variable. JavaScript let myVar: number = 42; console.log(typeof myVar); Output:numberApproach 2: Using instanceof OperatorThe instanceof operator is used to determine whether an object is an instance of a specific class or constructor function. This can be particularly useful for user-defined types.Example: In this example, we are using instanceof Operator to get the type of a variable. JavaScript class MyClass { // class definition } let myInstance = new MyClass(); if(myInstance instanceof MyClass){ console.log(`myInstance is an instance of class MyClass and its type is: ${typeof myInstance}`) } Output:myInstance is an instance of class MyClass and its type is: objectApproach 3: Using Type GuardsType guards in TypeScript allow you to narrow down the type of a variable within conditional blocks. These are particularly powerful because they enable TypeScript to recognize types in a way that impacts code flow analysis.Example: In this example, we are using Type Guards to get the type of a variable. JavaScript function isString(value: any): void { if (typeof value === "string") { console.log("It's a string!"); } else{ console.log(`Passed value is of ${typeof age} type.`) } } let greet: any = "Hello, TypeScript!"; const age: any = 20; isString(greet); isString(age); Output:It's a string! Passed value is of number type. Comment More infoAdvertise with us Next Article How to Get a Variable Type in TypeScript A amanv09 Follow Improve Article Tags : JavaScript Web Technologies TypeScript Similar Reads How to Declare Variables in TypeScript ? In TypeScript, a variable can be defined by specifying the data type of the value it is going to store. It will store the values of the specified data type only and throws an error if you try to store the value of any other data type. 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