Benchmark: Date.now() vs +new Date() test

Script Preparation code:

var timestamp = null;

Tests:

Date.now()
timestamp = Date.now();
new Date().getTime();
timestamp = +new Date();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Date.now()
new Date().getTime();

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36 OPR/97.0.0.0

Browser/OS: Opera 97 on Windows

View result in a separate tab

Test name	Executions per second
Date.now()	3215480.5 Ops/sec
new Date().getTime();	2156410.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks!

**What is tested on the provided JSON?**

The benchmark measures the performance difference between two approaches to get the current timestamp:

1. `Date.now()`
2. `new Date().getTime()` (which is equivalent to `+new Date()`)

These two methods are used to create a test case where we want to measure the execution time of the timestamp retrieval.

**Options compared**

The benchmark compares two options:

A) Using `Date.now()` directly
B) Using `new Date().getTime()` (which is equivalent to `+new Date()`, but with the `new` keyword)

**Pros and Cons of each approach:**

1. **Using `Date.now()`**
	* Pros:
		+ Simple and straightforward
		+ Fast, as it's a direct call on the `Date` object
	* Cons:
		+ May not be as readable or maintainable as other options
2. **Using `new Date().getTime()` (or `+new Date()` )**
	* Pros:
		+ More explicit and readable than using `Date.now()`
		+ Some people consider it more idiomatic JavaScript
	* Cons:
		+ May have a slight performance overhead due to the creation of a new `Date` object

**Library and syntax**

Neither of these approaches uses any external libraries or special JavaScript features. The benchmark only relies on built-in JavaScript functions.

**Other considerations**

The benchmark also considers other factors, such as:

* Browser and device platform (Opera 97 in this case)
* Execution speed per second (`ExecutionsPerSecond` metric)

**Alternatives**

If you were to write a similar benchmark for other timestamp-related methods or approaches, some alternatives might include:

* Using `performance.now()` instead of `Date.now()`
* Comparing different string representations of timestamps (e.g., ISO 8601 vs. Unix time)
* Testing the performance of different data structures for storing and retrieving timestamps

Keep in mind that this benchmark is relatively simple and focused on the specific comparison between these two approaches. More comprehensive benchmarks might explore other aspects of JavaScript's timestamp capabilities.

Related benchmarks:

Date.now() vs +new Date() test (version: 0)

Comparing performance of: Date.now() vs new Date().getTime();

Created: one year ago by: Guest

Jump to the latest result

Date.now()

new Date().getTime();

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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