How to get the first key name of a JavaScript object ? Last Updated : 10 Jan, 2025 Summarize Comments Improve Suggest changes Share Like Article Like Report In JavaScript, accessing the first key name of an object involves identifying the initial property defined within that object. This concept is useful when you need to interact with or manipulate object properties in a specific order, particularly when the sequence of properties is relevant.Here we have some common approaches to get the first key name of a JavaScript object:Table of ContentUsing Object.keys() MethodUsing for...in LoopUsing Object.keys() MethodThe Object.keys() method retrieves an array of a JavaScript object's keys. To get the first key name, access the first element of this array using [0]. This approach is straightforward and commonly used to obtain the initial key in an object.SyntaxObject.keys(obj);Example: In this example, the Object.keys(obj)[0] retrieves the first key from the object obj. Here, it returns a. JavaScript const obj = { a: 1, b: 2, c: 3 }; // Object with keys const firstKey = Object.keys(obj)[0]; // Get first key console.log(firstKey); // "a" Outputa Using for...in LoopThe for...in loop iterates over the enumerable properties of a JavaScript object. To get the first key name, you can use this loop and break immediately after the first iteration, capturing the first key. This approach is simple and direct for accessing the initial key.Syntaxfor (let i in obj1) { // Prints all the keys in // obj1 on the console console.log(i);}Example: In this example we use a for...in loop to capture the first key of inputObject. It logs "1" after exiting the loop immediately upon finding the first key. JavaScript const inputObject = { 1: 'JavaScript', 2: 'Python', 3: 'HTML' }; console.log("The first key name of the object is: "); let firstKey; for (let key in inputObject) { firstKey = key; // Capture the first key break; // Exit loop after the first key } console.log(firstKey); // Output: "1" OutputThe first key name of the object is: 1 JavaScript is best known for web page development but it is also used in a variety of non-browser environments. You can learn JavaScript from the ground up by following this JavaScript Tutorial and JavaScript Examples. Comment More infoAdvertise with us Next Article How to get all the methods of an object using JavaScript? P PranchalKatiyar Follow Improve Article Tags : JavaScript Web Technologies JavaScript-Questions Similar Reads How to get the Class Name of an Object in JavaScript In this article, we will learn how we can get the class Name of an Object with multiple approaches in JavaScript. In JavaScript, determining an object's class name can be done using multiple approaches. The constructor property of an object reveals the function that created it, while the instanceof 3 min read How to get the size of a JavaScript object ? In this article, we will see the methods to find the size of a JavaScript object. These are the following ways to solve the problem: Table of Content Using Object.keys() methodUsing Object.objsize() methodUsing Object.entries() methodUsing Object.values() methodUsing Object.keys() methodWe can get t 2 min read How to get the last item of JavaScript object ? In this article, we will learn how to get the last item of a Javascript object. Given a JavaScript object and the task is to get the last element of the JavaScript object. This can be done by the following methods: Using Object.keys() methodUsing for loopmethodApproach 1: Use Object.keys() method to 2 min read How to get all the methods of an object using JavaScript? In this article, we will learn how to get all the methods of an object using JavaScript. In JavaScript, we can get all the methods of an object by iterating over each object and checking if its property value is a function. An HTML document contains some methods and the task is to get all methods of 2 min read How to print the content of an object in JavaScript ? To print the content of an object in JavaScript we will use JavaScript methods like stringify, object.values and loops to display the required data. Let's first create a JavaScript Object containing some key-values as given below: JavaScript // Given Object const obj = { name: 'John', age: 30, city: 3 min read How to get property descriptors of an object in JavaScript ? Here, we are going to discuss the property descriptors of an Object in JavaScript. The Object.getOwnPropertyDescriptor() method returns an object describing a specific property on a given object. A JavaScript object can be created in many ways and its properties can be called by using property descr 2 min read Like