Benchmark: Fastest way to check if object is empty with 3 types of checks

Script Preparation code:

var xxx = {}

Tests:

object.keys()
Object.keys(xxx) === 0
JSON.stringify()
JSON.stringify(xxx) === "{}"
iterate over props
let isEmpty = true; for (const key in xxx) { isEmpty = false; break; } return isEmpty;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
object.keys()
JSON.stringify()
iterate over props

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one month ago):

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its various components.

**Benchmark Overview**

The provided benchmark measures which method is the fastest for checking if an object is empty, using three different approaches: `object.keys()`, `JSON.stringify()`, and iterating over the object's properties (`for...in` loop).

**Approach 1: `object.keys()`**

This approach uses the built-in `object.keys()` method to get an array of the object's property names. If the array is empty, it means the object is empty.

Pros:

* Simple and concise code
* Works on most browsers (note that some older browsers may not support this method)

Cons:

* May be slower than other approaches for very large objects, as it needs to iterate over all properties

**Approach 2: `JSON.stringify()`**

This approach uses the `JSON.stringify()` method to convert the object to a JSON string. An empty object will result in an empty string.

Pros:

* Can work with nested objects and arrays
* Can be faster than iterating over properties for very large objects, as it only needs to serialize the entire object

Cons:

* May not work correctly if the object contains non-serializable values (e.g., functions or undefined)
* May be slower on some browsers due to stringification overhead

**Approach 3: Iterating over properties (`for...in` loop)**

This approach uses a traditional `for...in` loop to iterate over the object's properties. If any property is not empty, it sets a flag and exits the loop.

Pros:

* Works correctly for all objects, regardless of their size or complexity
* Can be faster than other approaches for very large objects, as it only needs to iterate over non-empty properties

Cons:

* More verbose code compared to `object.keys()` or `JSON.stringify()`

**Library Used: None**

There are no external libraries used in this benchmark.

**Special JavaScript Features/ Syntax: None**

None of the test cases use special JavaScript features or syntax, such as async/await, Promises, or decorators.

**Alternatives**

Other approaches to checking if an object is empty could include:

* Using a `Set` or `Map` object to check for emptiness (e.g., `new Set(Object.keys(xxx)).size === 0`)
* Using a recursive function to iterate over the object's properties
* Using a library like Lodash, which provides utility functions for working with objects

Note that the choice of approach depends on the specific use case and requirements of the application.

Latest run results:

Run details: (Test run date: 8 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Linux

View result in a separate tab

Test name	Executions per second
object.keys()	9079691.0 Ops/sec
JSON.stringify()	6776522.5 Ops/sec
iterate over props	23494184.0 Ops/sec

Related benchmarks:

Fastest way to check if object is empty with 3 types of checks (version: 0)

You don't need to make add for loops in your test scenarios, the benchmark does it itself.

Comparing performance of: object.keys() vs JSON.stringify() vs iterate over props

Created: 8 months ago by: Guest

Jump to the latest result

object.keys()

JSON.stringify()

iterate over props

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one month ago):