Benchmark: Date JS VS Date-Fns - differenceInSeconds

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/npm/moment@2.29.4/moment.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/date-fns/cdn.min.js"></script>

Script Preparation code:

var unix = 1724409214;

Tests:

Date JS
const keyEffectiveDateStart = new Date('2025-07-21T11:42:05.322Z'); const keyEffectiveDateEnd = new Date('2025-07-21T12:35:01.233Z'); const secondsTillKeyEnd = (keyEffectiveDateEnd.getTime() - keyEffectiveDateStart.getTime()) / 1000;
Date-Fns
const keyEffectiveDateStart = new Date('2025-07-21T11:42:05.322Z'); const keyEffectiveDateEnd = new Date('2025-07-21T12:35:01.233Z'); const secondsTillKeyEnd = dateFns.differenceInSeconds(keyEffectiveDateEnd, keyEffectiveDateStart);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Date JS
Date-Fns

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Safari/537.36

Browser/OS: Chrome 138 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Date JS	2076046.2 Ops/sec
Date-Fns	1340965.4 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 9 months ago):

LLMs can make mistakes. Check important info.

The provided benchmark compares the performance of two different approaches to calculating the difference in seconds between two dates in JavaScript: using the native JavaScript `Date` object and using the `date-fns` library's `differenceInSeconds` function.

### Options Compared:
1. **Date JS (Native JavaScript)**:
   - This approach leverages the built-in `Date` object in JavaScript. It calculates the difference between two `Date` instances by converting them to milliseconds since the Unix epoch and then performing subtraction.
   - **Formula Used**: 
     ```javascript
     const secondsTillKeyEnd = (keyEffectiveDateEnd.getTime() - keyEffectiveDateStart.getTime()) / 1000;
     ```

2. **Date-Fns**:
   - This approach makes use of the `date-fns` library, a popular utility library for date manipulation in JavaScript, which provides a functional programming style and is optimized for performance.
   - **Function Used**: `differenceInSeconds`
   - **Formula Used**:
     ```javascript
     const secondsTillKeyEnd = dateFns.differenceInSeconds(keyEffectiveDateEnd, keyEffectiveDateStart);
     ```

### Pros and Cons:

**Date JS (Native JavaScript)**
- **Pros**:
  - No additional libraries are required, which reduces the size of the application and the number of dependencies.
  - Generally faster as there is no overhead of function calls.
  
- **Cons**:
  - Requires manual handling of date conversions, which can lead to errors.
  - More verbose and less intuitive for complex date manipulations compared to utility libraries like `date-fns`.

**Date-Fns**
- **Pros**:
  - Designed for readability and ease of use, especially with multiple date manipulations.
  - Provides additional functions for various date operations (e.g., formatting, parsing, difference calculations).
  - More optimized for handling edge cases around date arithmetic (e.g., time zones, leap years).

- **Cons**:
  - Additional dependency, which may not be ideal for minimal projects.
  - Slightly slower performance due to function overhead, especially in tight loops or high-frequency calls.

### Other Considerations:
- **Dependencies and Bundle Size**: Adding a utility library like `date-fns` increases the application's bundle size, which can affect performance, especially on initial load.
- **Execution Environments**: Benchmarks might perform differently across different environments (e.g., browsers, devices). For example, the tests were executed in Chrome 138 on macOS, and results could differ in other browsers or devices.
  
### Alternatives:
- **Moment.js**: Previously a very popular date manipulation library, but now in maintenance mode. It is larger and can be heavier than `date-fns`.
- **Luxon**: Another date manipulation library that leverages the `Intl` API to provide timezone awareness.
- **date-fns-tz**: An extension of `date-fns` for timezone support if that functionality is needed.

In summary, the benchmark illustrates the trade-offs between using the native JavaScript `Date` object and a utility library like `date-fns`. Each approach has its strengths and weaknesses depending on the context in which they are used. For scenarios requiring simple date difference calculations, the native method can be faster; however, for more complex manipulations, a library might be worth the overhead.

Related benchmarks:

Date JS VS Date-Fns - differenceInSeconds (version: 1)

Comparing performance of: Date JS vs Date-Fns

Created: 9 months ago by: Guest

Jump to the latest result

Date JS

Date-Fns

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 9 months ago):