Filter an Array of Objects in JavaScript By a Key or Property

It's a very common requirement that we want to filter an array of objects in JavaScript by a specific key or property value. That's why, JavaScript has a filter() method for arrays.

This method returns a new array with those objects that meet a certain condition.

Filter an Array of Objects By a Property

          const people = [
    { name: 'Alice', age: 25 },
    { name: 'Bob', age: 30 },
    { name: 'Charlie', age: 20 },
    { name: 'David', age: 35 },
]

const filtered = people.filter((person) => person.age >= 30)

console.log(filtered)
// Output: [{ name: 'Bob', age: 30 }, { name: 'David', age: 35 }]

        

I have a people array with 4 objects. Each object has name and age properties.

I want to get the people whose age is 30 or above. I can get those people by using the filter() method.

I am calling the filter method on the people array and returning true if the person.age property is equal to 30 or greater.

If the age is equal to 30 or greater, it will be added to the filtered array.

Finally, I am getting an array with 2 objects where the age property value is equal to or greater than 30.

Also Read: Loop Through an Array of Objects in JavaScript

Filter an Array of Objects With Multiple Conditions

You can use the filter() method to filter out an array of objects with multiple conditions i.e. by checking each object against multiple criteria.

          const products = [
    { name: 'Chair', price: 50, category: 'Furniture' },
    { name: 'Table', price: 140, category: 'Furniture' },
    { name: 'Lamp', price: 30, category: 'Lighting' },
    { name: 'Desk', price: 200, category: 'Furniture' },
    { name: 'Mirror', price: 80, category: 'Decor' },
]

const filtered = products.filter((product) => {
    const priceCondition = product.price >= 50 && product.price <= 150
    const categoryCondition = product.category === 'Furniture'

    return priceCondition && categoryCondition
})

console.log(filtered)
// Output: [{ name: 'Chair', price: 50, category: 'Furniture' }, { name: 'Table', price: 140, category: 'Furniture' }]

        

Here, I am filtering the products array by checking if the product's price is within the specified range and if the product's category matches the desired category.

In this case, I am checking if the product's price is between 50 to 150 and the product's category is equal to "Furniture".

I am getting an array with 2 products that match both of those conditions.