How to check if an object is empty in javascript

There are a few ways to check if an object is empty in Javascript.
But I care about performance and readability.

The fastest way is to use a for...in loop.
You could use the below code snippet as a utility function.

function isEmpty(obj) {
    for(let key in obj) {
        if(obj.hasOwnProperty(key))
            return false;
    }
    return true;
}

My favorite way for readability reasons and it's still high performing is using Object.keys.

function isEmpty(obj) {
    return Object.keys(obj).length === 0
}

Note: Object.keys is faster than using Object.entries.

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