Benchmark: new Date from UNIX timestamp vs new Date from ISO string

Tests:

new Date
new Date(1576610077 * 1000);
Date.parse
Date.parse('2019-07-31T13:03:00.000Z');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
new Date
Date.parse

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 27 days ago)

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_1_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.1.1 Mobile/15E148 Safari/604.1

Browser/OS: Mobile Safari 18 on iOS 18.1.1

View result in a separate tab

Test name	Executions per second
new Date	27258446.0 Ops/sec
Date.parse	39613136.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks, which are small tests designed to measure the performance of specific JavaScript code snippets.

The benchmark provided in this example compares two ways of creating Date objects:

1. Using a UNIX timestamp (`new Date(1576610077 * 1000)`)
2. Using an ISO string (`Date.parse('2019-07-31T13:03:00.000Z')`)

**Benchmark Preparation Code**

The script preparation code is empty, which means that the benchmark starts from scratch each time it's run.

**Html Preparation Code**

The HTML preparation code is also empty, which suggests that this benchmark doesn't rely on any specific HTML setup or configuration.

**Library and Special Features**

1. `Date` object: The Date object is a built-in JavaScript object that provides methods for working with dates and times. In this benchmark, we're using the `new Date()` constructor to create Date objects from UNIX timestamps and ISO strings.
2. No special JS features or syntax are used in this benchmark.

**Comparison of Approaches**

The two approaches being compared have different pros and cons:

1. **UNIX timestamp**:
	* Pros: Easy to generate UNIX timestamps, widely available, can be easily parsed by JavaScript engines.
	* Cons: May not be as readable or human-friendly as ISO strings.
2. **ISO string**:
	* Pros: More readable and human-friendly than UNIX timestamps, allows for easy date parsing without relying on specific engine support.
	* Cons: Requires a more complex format string to generate, may require additional processing steps.

In general, using an ISO string can be beneficial when readability and maintainability are crucial. However, if performance is the primary concern, using a UNIX timestamp might be a better choice due to its simplicity and wide availability.

**Alternatives**

If you need to benchmark Date object creation performance, here are some alternative approaches:

1. Use a different date format (e.g., RFC 2822).
2. Compare the performance of different JavaScript engines or implementations (e.g., V8 vs SpiderMonkey).
3. Measure the performance of other methods for creating Date objects (e.g., using the `Date.now()` method).

Keep in mind that the choice of approach depends on your specific use case and requirements.

**Other Considerations**

When benchmarking JavaScript code, consider the following:

1. Use a consistent test environment to minimize variability.
2. Optimize test code for performance and readability.
3. Avoid introducing unnecessary overhead or delays during testing.
4. Run benchmarks multiple times with warm-up cycles to get accurate results.
5. Analyze the output to identify trends and areas for improvement.

Related benchmarks:

new Date from UNIX timestamp vs new Date from ISO string (version: 0)

Comparing performance of: new Date vs Date.parse

Created: 5 years ago by: Guest

Jump to the latest result

new Date

Date.parse

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):