Benchmark: Object.keys vs Object.entries vs Object.values

Script Preparation code:

var someObject = { a: 123, b: 456, c: 789 };

Tests:

Object.keys
var x = Object.keys(someObject);
Object.entries
var x = Object.entries(someObject);
Object.values
var x = Object.values(someObject);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.keys
Object.entries
Object.values

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36

Browser/OS: Chrome 139 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Object.keys	80425160.0 Ops/sec
Object.entries	47843772.0 Ops/sec
Object.values	60428832.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**What is being tested?**

The provided JSON represents a benchmark test case on MeasureThat.net, which compares the performance of three different approaches to iterate over an object's properties: `Object.keys()`, `Object.entries()`, and `Object.values()`.

**Options compared:**

1. **Object.keys()**: Returns an array of strings representing the property names of an object.
2. **Object.entries()**: Returns an array of two-element arrays, where each inner array contains a property name and its corresponding value as a string.
3. **Object.values()**: Returns an array containing the values of an object.

**Pros and Cons:**

1. **Object.keys()**:
	* Pros: Simple to use and understand, easy to iterate over properties by their names.
	* Cons: Returns property names only, not the corresponding values or arrays. Iterating over the result requires additional parsing.
2. **Object.entries()**:
	* Pros: Returns both property names and values as an array of two-element arrays, making it easier to access and manipulate both.
	* Cons: Returns a more complex data structure than `Object.keys()`, which can be slower for iteration due to the added overhead.
3. **Object.values()**:
	* Pros: Returns only the object's values, which can be useful in certain scenarios.
	* Cons: Does not provide access to property names, requiring additional parsing or lookup.

**Library and its purpose**

None of the benchmarked functions use a specific library. They are built-in JavaScript methods for working with objects.

**Special JS feature or syntax**

None mentioned. The benchmark only tests standard JavaScript features and syntax.

**Other alternatives**

While not explicitly listed in the benchmark, other ways to iterate over an object's properties include:

1. Using `for...in` loop: Iterates over property names using a loop.
2. Using `Object.keys()` with a callback function: Allows iterating over property values while still accessing their names.

However, these alternatives are not compared in this specific benchmark.

**Benchmark preparation code**

The provided JavaScript script creates an object named `someObject` and assigns it to the variables used in each benchmarked method:

```javascript
var someObject = { a: 123, b: 456, c: 789 };
```

This object serves as the test data for the comparison.

Related benchmarks:

Object.keys vs Object.entries vs Object.values (version: 0)

Comparing performance of: Object.keys vs Object.entries vs Object.values

Created: 2 years ago by: Guest

Jump to the latest result

Object.keys

Object.entries

Object.values

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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