Benchmark: Date vs Dayjs (not casting to date)

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/npm/dayjs@1/dayjs.min.js"></script>

Tests:

Date
new Date('2000-01-01' + 'T00:00')
dayjs
dayjs('2000-01-01', { utc: true })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Date
dayjs

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:136.0) Gecko/20100101 Firefox/136.0

Browser/OS: Firefox 136 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
Date	27244694.0 Ops/sec
dayjs	4295225.5 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated one month ago):

LLMs can make mistakes. Check important info.

The benchmark defined in the provided JSON compares the performance of two different methods for creating date objects in JavaScript: the built-in `Date` constructor and the `dayjs` library. Both methods are used to represent a date but do so with different implementations and features.

### Options Compared

1. **Built-in Date Constructor**:
   - **Test Definition**: `new Date('2000-01-01' + 'T00:00')`
   - **Test Name**: Date
   - This method calls the native JavaScript `Date` object and creates a new date representing January 1, 2000. The `T00:00` is appended to specify the time, which sets the time to midnight.

2. **Day.js Library**:
   - **Test Definition**: `dayjs('2000-01-01', { utc: true })`
   - **Test Name**: dayjs
   - This method uses the `dayjs` library, a lightweight JavaScript date library, to create the same date. The `{ utc: true }` option specifies that the date should be created in Coordinated Universal Time (UTC).

### Pros and Cons

#### Built-in Date Constructor
- **Pros**:
  - Performance: As seen in the benchmark results, the native `Date` constructor performs significantly better (around 27 million executions per second).
  - No additional dependencies: Using the built-in `Date` object means there's no need to include external libraries, leading to smaller bundle sizes.
  
- **Cons**:
  - Complexity: Handling time zones and date manipulations can be complex and sometimes counterintuitive, as the `Date` object does not natively support all operations simply or elegantly.
  - Limited functionality: While the built-in `Date` object covers basic needs, more advanced operations (like formatting, relative dates, etc.) can be cumbersome.

#### Day.js Library
- **Pros**:
  - Simplicity and readability: Day.js allows for easier manipulation and formatting of dates, often leading to more concise and understandable code.
  - Extended functionality: The library offers an extensive range of features, including parsing, manipulating, and displaying dates in different formats and time zones.
  
- **Cons**:
  - Performance: The results indicate that Day.js is significantly slower (around 4.3 million executions per second) when compared to the built-in `Date`.
  - Dependency overhead: Including Day.js increases the size of your application and introduces external dependencies that need to be managed, which can affect loading times and might introduce compatibility issues.

### Other Considerations

Using the `Date` object can be a better choice for performance-critical applications due to its speed and lack of dependencies. However, for applications that rely heavily on date manipulation, a library like Day.js (or alternatives like Moment.js, Luxon, or date-fns) can enable cleaner code and more intuitive date handling.

### Alternatives

- **Moment.js**: A well-established library with comprehensive date manipulation capabilities but with a larger bundle size and slower performance compared to more modern libraries.
- **date-fns**: Offers a modular approach to date functions, allowing developers to import only what they need, reducing bundle size.
- **Luxon**: Built on the Internationalization API, it provides immutable date/time handling and supports advanced time zone operations.

In conclusion, the choice between using the native `Date` object and a library like Day.js depends on the specific needs of the application, including considerations around performance, functionality, and code maintainability.

Related benchmarks:

Date vs Dayjs (not casting to date) (version: 1)

Comparing performance of: Date vs dayjs

Created: one month ago by: Guest

Jump to the latest result

Date

dayjs

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated one month ago):